Also refactor the tests architecture to have real tests interacting from outside the directive.

The order of watchers definition set the order in which their callback will be called when 2 watched
values are modified simultaneously. If the slider value is changed along with the precision options,
we want the value to be parsed with the new precision.

Closes #207

Add a draggableRangeOnly options. 

As described in #196 and #199

The URL has changed as they repository has been moved to its own organisation.

Add keyboard support [WIP]

 # remove jquery

Add a getSelectionBarColor options