Sets cursors for slider elements: trail, handler, slider itself
CDB-958 #fixes Stops the propagation to fix dragging problems in IE
Merge branch 'feature/CDB-363_torque_integration' of git://github.com/CartoDB/cartodb.js into feature/CDB-363_torque_integration

* 'feature/CDB-363_torque_integration' of git://github.com/CartoDB/cartodb.js:
  time_slider support number and date values CDB-929
  updated torque