Added some indicators to give a more buttonlike presence

I needed more visual feedback for users on the switch itself therefore I've
added some simple indicators with additional classes.
Which give the switch a more buttonlike presence. 
Based on simple characters which are added with CSS3 :before selector.

One may choose from:

.indicator-angle
.indicator-pipe
.indicator-on-off

I wanted to give back to the community, so hopefully it's useful for anyone