New features in 'mail' module

I've added a few features to the 'mail' module [1] because I need them,
and hope you'll need them too :slight_smile:

1. Support for MIME attachments (content-type: octet/stream). This may
   sound pretty crazy, but it goes like this: "Send me the file please".

2. Support for custom headers (inspired by Dag ranting about #1 on IRC :slight_smile:

3. Support for specifying a non-standard SMTP port.

4. Support for specifying e-mail address with phrase portion (e.g.
   "John Doe <john@example.com>" for those mails that need to look good
   to a manager. :slight_smile:

An example playbook and output can be found at [1].

Regards,

        -JP

[1] https://github.com/ansible/ansible/pull/1752

w00t !