Monitor template

Hello,

A lot of changes here, which boil down to these:

    * Fix issue #9: this role no longer creates groups.
    * Filled galaxy meta info.
    * Testing with vagrant.
    * Generic monitor and mail template and tasks revamp.

Please read the README for more clarification on the new and deprecated variables.

Thank you.

PS: Can you please add this role the galaxy.ansible.com? Thank you!