##### SUMMARY
win_domain_user always returns changed if a password is specified.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
win_domain_user

##### ANSIBLE VERSION
```paste below
ansible 2.8.1
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/user/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.7.3 (default, Mar 26 2019, 21:43:19) [GCC 8.2.1 20181127]
```

##### CONFIGURATION

##### OS / ENVIRONMENT

ArchLinux

##### STEPS TO REPRODUCE
```yaml
- name: Set AD User Password
      win_domain_user:
        name: '{{ user_name }}'
        password: '{{ password }}'
        state: present
- name: Set AD User Password again
      win_domain_user:
        name: '{{ user_name }}'
        password: '{{ password }}'
        state: present
```

##### EXPECTED RESULTS
The 2nd task to show as not changed.

##### ACTUAL RESULTS
The 2nd task shows as changed, even though the password was already set.
returned: always
    type: str
    sample: nick
password_expired:
    description: true if the account password has expired
    returned: always
    type: bool
    sample: false
password_updated:
    description: true if the password changed during this execution
    returned: always
    type: bool
    sample: true
postal_code:
    description: The user postal code
    returned: always
    type: str
    sample: 46033
sid:
    description: The SID of the account
    returned: always
    type: str
    sample: S-1-5-21-2752426336-228313920-2202711348-1175
state:
    description: The state of the user account
    returned: always
    type: str
    sample: present
state_province:
    description: The user state or province