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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

try:
        smtp.ehlo()
    except smtplib.SMTPException as e:
        module.fail_json(rc=1, msg='Helo failed for host %s:%s: %s' % (host, port, to_native(e)), exception=traceback.format_exc())
    if int(code) > 0:
        if not secure_state and secure in ('starttls', 'try'):
            if smtp.has_extn('STARTTLS'):
                try:
                    smtp.starttls()
                    secure_state = True
                except smtplib.SMTPException as e:
                    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())
                try:
                    smtp.ehlo()
                except smtplib.SMTPException as e:
                    module.fail_json(rc=1, msg='Helo failed for host %s:%s: %s' % (host, port, to_native(e)), exception=traceback.format_exc())
            else:
                if secure == 'starttls':
                    module.fail_json(rc=1, msg='StartTLS is not offered on server %s:%s' % (host, port))
    if username and password:
        if smtp.has_extn('AUTH'):
            try:
                smtp.login(username, password)
            except smtplib.SMTPAuthenticationError:
                module.fail_json(rc=1, msg='Authentication to %s:%s failed, please check your username and/or password' % (host, port))
            except smtplib.SMTPException:
                module.fail_json(rc=1, msg='No Suitable authentication method was found on %s:%s' % (host, port))
        else:
            module.fail_json(rc=1, msg="No Authentication on the server at %s:%s" % (host, port))