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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

secure = module.params.get('secure')
    timeout = module.params.get('timeout')
    code = 0
    secure_state = False
    sender_phrase, sender_addr = parseaddr(sender)
    if not body:
        body = subject
    try:
        if secure != 'never':
            try:
                if PY3:
                    smtp = smtplib.SMTP_SSL(host=host, port=port, timeout=timeout)
                else:
                    smtp = smtplib.SMTP_SSL(timeout=timeout)
                code, smtpmessage = smtp.connect(host, port)
                secure_state = True
            except ssl.SSLError as e:
                if secure == 'always':
                    module.fail_json(rc=1, msg='Unable to start an encrypted session to %s:%s: %s' %
                                               (host, port, to_native(e)), exception=traceback.format_exc())
            except Exception:
                pass
        if not secure_state:
            if PY3:
                smtp = smtplib.SMTP(host=host, port=port, timeout=timeout)
            else:
                smtp = smtplib.SMTP(timeout=timeout)
            code, smtpmessage = smtp.connect(host, port)
    except smtplib.SMTPException as e:
        module.fail_json(rc=1, msg='Unable to Connect %s:%s: %s' % (host, port, to_native(e)), exception=traceback.format_exc())