New delegation management module

There is a new delegation management module placed in the plugins folder:

    plugins/modules/ipadelegation.py

The delegation module allows to ensure presence and absence of delegations
and manage delegation attributes.

Here is the documentation for the module:

    README-delegation.md

New example playbooks have been added:

    playbooks/delegation/delegation-absent.yml
    playbooks/delegation/delegation-present.yml
    playbooks/delegation/delegation-member-absent.yml
    playbooks/delegation/delegation-member-present.yml

New tests for the module:

    tests/delegation/test_delegation.yml

README-delegation.md

@@ -0,0 +1,157 @@
+Delegation module
+=================
+
+Description
+-----------
+
+The delegation module allows to ensure presence, absence of delegations and delegation attributes.
+
+
+Features
+--------
+
+* Delegation management
+
+
+Supported FreeIPA Versions
+--------------------------
+
+FreeIPA versions 4.4.0 and up are supported by the ipadelegation module.
+
+
+Requirements
+------------
+
+**Controller**
+* Ansible version: 2.8+
+
+**Node**
+* Supported FreeIPA version (see above)
+
+
+Usage
+=====
+
+Example inventory file
+
+```ini
+[ipaserver]
+ipaserver.test.local
+```
+
+
+Example playbook to make sure delegation "basic manager attributes" is present:
+
+```yaml
+---
+- name: Playbook to manage IPA delegation.
+  hosts: ipaserver
+  become: yes
+
+  tasks:
+  - ipadelegation:
+      ipaadmin_password: SomeADMINpassword
+      name: "basic manager attributes"
+      permission: read
+      attribute:
+      - businesscategory
+      - employeetype
+      group: managers
+      membergroup: employees
+```
+
+
+Example playbook to make sure delegation "basic manager attributes" is absent:
+
+```yaml
+---
+- name: Playbook to manage IPA delegation.
+  hosts: ipaserver
+  become: yes
+
+  tasks:
+  - ipadelegation:
+      ipaadmin_password: SomeADMINpassword
+      name: "basic manager attributes"
+      state: absent
+```
+
+
+Example playbook to make sure "basic manager attributes" member attributes employeetype and employeenumber are present:
+
+```yaml
+---
+- name: Playbook to manage IPA delegation.
+  hosts: ipaserver
+  become: yes
+
+  tasks:
+  - ipadelegation:
+      ipaadmin_password: SomeADMINpassword
+      name: "basic manager attributes"
+      attribute:
+      - employeenumber
+      - employeetype
+      action: member
+```
+
+
+Example playbook to make sure "basic manager attributes" member attributes employeetype and employeenumber are absent:
+
+```yaml
+---
+- name: Playbook to manage IPA delegation.
+  hosts: ipaserver
+  become: yes
+
+  tasks:
+  - ipadelegation:
+      ipaadmin_password: SomeADMINpassword
+      name: "basic manager attributes"
+      attribute:
+      - employeenumber
+      - employeetype
+      action: member
+      state: absent
+```
+
+
+Example playbook to make sure delegation "basic manager attributes" is absent:
+
+```yaml
+---
+- name: Playbook to manage IPA delegation.
+  hosts: ipaserver
+  become: yes
+
+  tasks:
+  - ipadelegation:
+      ipaadmin_password: SomeADMINpassword
+      name: "basic manager attributes"
+      state: absent
+```
+
+
+Variables
+---------
+
+ipadelegation
+-------
+
+Variable | Description | Required
+-------- | ----------- | --------
+`ipaadmin_principal` | The admin principal is a string and defaults to `admin` | no
+`ipaadmin_password` | The admin password is a string and is required if there is no admin ticket available on the node | no
+`name` \| `aciname` | The list of delegation name strings. | yes
+`permission` \| `permissions` |  The permission to grant `read`, `read,write`, `write`]. Default is `write`. | no
+`attribute` \| `attrs` | The attribute list to which the delegation applies. | no
+`membergroup` \| `memberof` | The user group to apply delegation to. | no
+`group` | User group ACI grants access to. | no
+`action` | Work on delegation or member level. It can be on of `member` or `delegation` and defaults to `delegation`. | no
+`state` | The state to ensure. It can be one of `present`, `absent`, default: `present`. | no
+
+
+Authors
+=======
+
+Thomas Woerner