Bowerizing

Changes and adjustments based on Issue [#66](https://github.com/drublic/css-modal/issues/66) which also includes aspects from [#58](https://github.com/drublic/css-modal/pull/58).

A couple of notes:

- Sass vars now have a ``!default`` flag allowing authors to override them from an outside source.
- Theming "plain screen" involves another ``@extend`` placeholder (this can be improved upon as we go). The ``%modal-theme`` is your general/global defaults. Other separated placeholders can become more specific.
- Grunt has been given some steroids and now includes MatchDep (So you don't have to add load task commands in your ``Gruntfile.js``) and Live Reload because, hey, we like instant feedback right?
- Eventually some mixins and functions should be added to manage the complexity/prefix grossness of the transitions and animations etc. Maybe adding [auto prefixer](https://github.com/grayghostvisuals/Effeckt.css/blob/gh-pages/Gruntfile.js#L48-L64) would be better suited and a more maintainable option going forward.

Ok now lets discuss :metal: