##### SUMMARY
Can functionality be added so that "Associable Object Types" can be configured for a tag category please?

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
vmware_category

##### ADDITIONAL INFORMATION
Perhaps the module could be extended to include a list, examples below;
```
- name: 'Create a Category'
  connection: 'local'
  vmware_category:
    hostname: '{{ ansible_host }}'
    username: '{{ ansible_vcenter_username }}'
    password: '{{ ansible_vcenter_password }}'
    category_name: "sas_luns"
    category_description: "SAS LUNS"
    category_cardinality: 'multiple'
    associable_object_types:
         - Datastore
         - Datastore Cluster
    state: present
    validate_certs: '{{ validate_certs }}'

- name: 'Create a Category'
  connection: 'local'
  vmware_category:
    hostname: '{{ ansible_host }}'
    username: '{{ ansible_vcenter_username }}'
    password: '{{ ansible_vcenter_password }}'
    category_name: "Region 1"
    category_description: "Region"
    category_cardinality: 'multiple'
    associable_object_types:
         - All objects
    state: present
    validate_certs: '{{ validate_certs }}'
```
The type of Associable Object Types in vSphere 6.7 are:
All objects
Folder
Cluster
Datacenter
Datastore
Datastore Cluster
Distributed Port Group
Distributed Switch
Host
Content Library
Library item
Network
Resource Pool
vApp
Virtual Machine

"""Create category."""
        category_spec = self.category_service.CreateSpec()
        category_spec.name = self.category_name
        category_spec.description = self.params.get('category_description')
        if self.params.get('category_cardinality') == 'single':
            category_spec.cardinality = CategoryModel.Cardinality.SINGLE
        else:
            category_spec.cardinality = CategoryModel.Cardinality.MULTIPLE
        category_spec.associable_types = set()
        try:
            category_id = self.category_service.create(category_spec)
        except Error as error:
            self.module.fail_json(msg="%s" % self.get_error_message(error))
        if category_id:
            self.module.exit_json(changed=True,
                                  category_results=dict(msg="Category '%s' created." % category_spec.name,
                                                        category_id=category_id))
        self.module.exit_json(changed=False,
                              category_results=dict(msg="No category created", category_id=''))
    def state_unchanged(self):