Timepicker add hour and minute sliders

Change Timepicker into two sliders, one for selecting specific hour, the other one for specific minute.

For further reference on Timepicker slider behavior see ->
http://trentrichardson.com/examples/timepicker/

For further reference on Timepicker format/style see ->
http://seiyria.com/bootstrap-slider/

Pictures attached for reference:
1. Studio_Timepicker_initial.png - Initial state shown when "Content Airtime Settings" modal opens up;
2. Studio_Timepicker_hour.png - Representation of selecting specific hour;
3. Studio_Timepicker_minute.png - Representation of selecting specific minute.