ipagroup: Fix changed flag, new test cases

The changed flag returned by ipagroup calls have not been correct. This
change fixes this. Addtitionally new test cases have been added to make
sure that the changed flag is correct.

plugins/modules/ipagroup.py

@@ -378,7 +378,10 @@ def main():
             try:
                 result = api_command(ansible_module, command, to_text(name),
                                      args)
-                if "completed" in result and result["completed"] > 0:
+                if "completed" in result:
+                    if result["completed"] > 0:
+                        changed = True
+                else:
                     changed = True
             except Exception as e:
                 ansible_module.fail_json(msg="%s: %s: %s" % (command, name,