Add specific support for other CMS

[sfaci]

Currently masc has specific support for WordPress and Drupal CMS but it's designed to support more CMS.
In the code you can encounter a CMS class where some generic methods are implemented and some specific classes to specific CMS.py (as WordPress.py and Drupal.py).

In fact, there is an empty class in the file Joomla.py but it's a good example about how to extends the CMS generic class to add specific support.

It would be great to improve masc adding support for another CMS or even some LMS (Moodle, for example) o any related known web application.