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##### SUMMARY
mail module does not send email with Date header. It should send email with "Date" header automatically without any manual email header manipulation.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
mail

##### ANSIBLE VERSION
```
ansible 2.8.1
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/home/yclee/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/dist-packages/ansible
  executable location = /usr/bin/ansible
  python version = 2.7.15+ (default, Nov 27 2018, 23:36:35) [GCC 7.3.0]
```

##### CONFIGURATION
(None)

##### OS / ENVIRONMENT
Ubuntu 18.04

##### STEPS TO REPRODUCE
N/A

##### EXPECTED RESULTS
email should have Date headers

##### ACTUAL RESULTS
email did not  have Date headers and I have to manually insert it

(successfully) taken.
version_added: '0.8'
options:
  from:
    description:
    - The email-address the mail is sent from. May contain address and phrase.
    type: str
    default: root
  to:
    description:
    - The email-address(es) the mail is being sent to.
    - This is a list, which may contain address and phrase portions.
    type: list
    default: root
    aliases: [ recipients ]
  cc:
    description:
    - The email-address(es) the mail is being copied to.
    - This is a list, which may contain address and phrase portions.
    type: list
  bcc:
    description:
    - The email-address(es) the mail is being 'blind' copied to.
    - This is a list, which may contain address and phrase portions.
    type: list
  subject:
    description:
    - The subject of the email being sent.
    required: yes
    type: str