ipadelegation: Allow execution of plugin in client host.

Update delegation README file and add tests for executing plugin with
`ipaapi_context` set to `client`.

A new test playbook can be found at:

    tests/delegation/test_delegation_client_context.yml

The new test file can be executed in a FreeIPA client host that is
not a server. In this case, it should be defined in the `ipaclients`
group, in the inventory file.

tests/delegation/test_delegation.yml

@@ -1,6 +1,6 @@
 ---
 - name: Test delegation
-  hosts: ipaserver
+  hosts: "{{ ipa_test_host | default('ipaserver') }}"
   become: true
 
   tasks:
@@ -10,12 +10,14 @@
   - name: Ensure test groups are absent
     ipagroup:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: managers,managers2,employees,employees2
       state: absent
 
   - name: Ensure delegation "basic manager attributes" is absent
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       state: absent
 
@@ -24,21 +26,25 @@
   - name: Ensure test group managers is present
     ipagroup:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: managers
 
   - name: Ensure test group managers2 is present
     ipagroup:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: managers2
 
   - name: Ensure test group employees is present
     ipagroup:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: employees
 
   - name: Ensure test group employees2 is present
     ipagroup:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: employees2
 
   # TESTS
@@ -46,6 +52,7 @@
   - name: Ensure delegation "basic manager attributes" is present
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       permission: read
       attribute:
@@ -58,6 +65,7 @@
   - name: Ensure delegation "basic manager attributes" is present again
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       permission: read
       attribute:
@@ -70,6 +78,7 @@
   - name: Ensure delegation "basic manager attributes" is present with different attribute employeetype
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       permission: read
       attribute:
@@ -82,6 +91,7 @@
   - name: Ensure delegation "basic manager attributes" is present with different attribute employeetype again
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       permission: read
       attribute:
@@ -94,6 +104,7 @@
   - name: Ensure delegation "basic manager attributes" member attribute departmentnumber is present
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       attribute:
       - departmentnumber
@@ -104,6 +115,7 @@
   - name: Ensure delegation "basic manager attributes" member attribute departmentnumber is present again
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       attribute:
       - departmentnumber
@@ -114,6 +126,7 @@
   - name: Ensure delegation "basic manager attributes" member attributes employeetype and employeenumber are present
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       attribute:
       - employeetype
@@ -125,6 +138,7 @@
   - name: Ensure delegation "basic manager attributes" member attributes employeetype and employeenumber are present again
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       attribute:
       - employeetype
@@ -136,6 +150,7 @@
   - name: Ensure delegation "basic manager attributes" member attributes employeenumber and employeetype are absent
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       attribute:
       - employeenumber
@@ -148,6 +163,7 @@
   - name: Ensure delegation "basic manager attributes" member attributes employeenumber and employeetype are absent again
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       attribute:
       - employeenumber
@@ -162,6 +178,7 @@
   - name: Ensure delegation "basic manager attributes" is present with different read,write permission
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       permission: read,write
       attribute:
@@ -174,6 +191,7 @@
   - name: Ensure delegation "basic manager attributes" is present with different read,write permission again
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       permission: read,write
       attribute:
@@ -186,6 +204,7 @@
   - name: Ensure delegation "basic manager attributes" is present with different group managers2
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       group: managers2
     register: result
@@ -194,6 +213,7 @@
   - name: Ensure delegation "basic manager attributes" is present with different group managers2 again
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       group: managers2
     register: result
@@ -202,6 +222,7 @@
   - name: Ensure delegation "basic manager attributes" is present with different membergroup employees2
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       membergroup: employees2
     register: result
@@ -210,6 +231,7 @@
   - name: Ensure delegation "basic manager attributes" is present with different membergroup employees2 again
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       membergroup: employees2
     register: result
@@ -218,6 +240,7 @@
   - name: Ensure delegation "basic manager attributes" fails with bad permission read,read
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       permission: read,read
     register: result
@@ -226,6 +249,7 @@
   - name: Ensure delegation "basic manager attributes" fails with bad permission read,write,write
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       permission: read,write,write
     register: result
@@ -234,6 +258,7 @@
   - name: Ensure delegation "basic manager attributes" fails with bad attribute businesscategory,businesscategory
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       attribute:
       - businesscategory
@@ -246,11 +271,13 @@
   - name: Ensure delegation "basic manager attributes" is absent
     ipadelegation:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: "basic manager attributes"
       state: absent
 
   - name: Ensure test groups are absent
     ipagroup:
       ipaadmin_password: SomeADMINpassword
+      ipaapi_context: "{{ ipa_context | default(omit) }}"
       name: managers,managers2,employees,employees2
       state: absent