[RFE] Allow multiple groups creation.

Adding an option `groups` to create multiple groups in one operation.
Adding tests (present/absent/external/nonposix) with server and
client context.
Simple example of `groups` option:
```
tasks:
- name: Ensure 2 groups are present
  ipagroup:
    ipaadmin_password: SomeADMINpassword
    groups:
    - name: group1
    - name: group2
```

Signed-off-by: Denis Karpelevich <dkarpele@redhat.com>

README-group.md

@@ -8,6 +8,9 @@ The group module allows to ensure presence and absence of groups and members of
 
 The group module is as compatible as possible to the Ansible upstream `ipa_group` module, but additionally offers to add users to a group and also to remove users from a group.
 
+## Note
+Ensuring presence (adding) of several groups with mixed types (`external`, `nonposix` and `posix`) requires a fix in FreeIPA. The module implements a workaround to automatically use `client` context if the fix is not present in the target node FreeIPA and if more than one group is provided to the task using the `groups` parameter. If `ipaapi_context` is forced to be `server`, the module will fail in this case.
+
 
 Features
 --------
@@ -71,6 +74,62 @@ Example playbook to add groups:
       name: appops
 ```
 
+These three `ipagroup` module calls can be combined into one with the `groups` variable:
+
+```yaml
+---
+- name: Playbook to handle groups
+  hosts: ipaserver
+
+  tasks:
+  - name: Ensure groups ops, sysops and appops are present
+    ipagroup:
+      ipaadmin_password: SomeADMINpassword
+      groups:
+      - name: ops
+        gidnumber: 1234
+      - name: sysops
+        user:
+        - pinky
+      - name: appops
+```
+
+You can also alternatively use a json file containing the groups, here `groups_present.json`:
+
+```json
+{
+  "groups": [
+    {
+      "name": "group1",
+      "description": "description group1"
+    },
+    {
+      "name": "group2",
+      "description": "description group2"
+    }
+  ]
+}
+```
+
+And ensure the presence of the groups with this example playbook:
+
+```yaml
+---
+- name: Tests
+  hosts: ipaserver
+  gather_facts: false
+
+  tasks:
+  - name: Include groups_present.json
+    include_vars:
+      file: groups_present.json
+
+  - name: Groups present
+    ipagroup:
+      ipaadmin_password: SomeADMINpassword
+      groups: "{{ groups }}"
+```
+
 Example playbook to add users to a group:
 
 ```yaml
@@ -112,11 +171,11 @@ Example playbook to add group members to a group:
 Example playbook to add members from a trusted realm to an external group:
 
 ```yaml
---
+---
 - name: Playbook to handle groups.
   hosts: ipaserver
-  became: true
-
+  
+  tasks:
   - name: Create an external group and add members from a trust to it.
     ipagroup:
       ipaadmin_password: SomeADMINpassword
@@ -127,6 +186,24 @@ Example playbook to add members from a trusted realm to an external group:
       - WINIPA\\Developers
 ```
 
+Example playbook to add nonposix and external groups:
+
+```yaml
+---
+- name: Playbook to add nonposix and external groups
+  hosts: ipaserver
+
+  tasks:
+  - name: Add nonposix group sysops and external group appops
+    ipagroup:
+      ipaadmin_password: SomeADMINpassword
+      groups:
+      - name: sysops
+        nonposix: true
+      - name: appops
+        external: true
+```
+
 Example playbook to remove groups:
 
 ```yaml
@@ -136,13 +213,29 @@ Example playbook to remove groups:
   become: true
 
   tasks:
-  # Remove goups sysops, appops and ops
+  # Remove groups sysops, appops and ops
   - ipagroup:
       ipaadmin_password: SomeADMINpassword
       name: sysops,appops,ops
       state: absent
 ```
 
+Example playbook to ensure groups are absent:
+
+```yaml
+---
+- name: Playbook to handle groups
+  hosts: ipaserver
+
+  tasks:
+  - name: Ensure groups ops and sysops are absent
+    ipagroup:
+      ipaadmin_password: SomeADMINpassword
+      groups:
+      - name: ops
+      - name: sysops
+      state: absent
+```
 
 Variables
 =========
@@ -152,8 +245,10 @@ 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
 `ipaapi_context` | The context in which the module will execute. Executing in a server context is preferred. If not provided context will be determined by the execution environment. Valid values are `server` and `client`. | no
-`ipaapi_ldap_cache` | Use LDAP cache for IPA connection. The bool setting defaults to yes. (bool) | no
+`ipaapi_ldap_cache` | Use LDAP cache for IPA connection. The bool setting defaults to <br/>. (bool) | no
 `name` \| `cn` | The list of group name strings. | no
+`groups` | The list of group dicts. Each `groups` dict entry can contain group variables.<br>There is one required option in the `groups` dict:| no
+&nbsp; | `name` - The group name string of the entry. | yes
 `description` | The group description string. | no
 `gid` \| `gidnumber` | The GID integer. | no
 `posix` | Create a non-POSIX group or change a non-POSIX to a posix group. `nonposix`, `posix` and `external` are mutually exclusive. (bool) | no