Seeking practically complete - reviews needed.

 - Added helper library (draggabilly) to handle dragging events (and all of it's dependencies)
 - Added angular bindings (directive) for draggabilly
 - Modified the css transform function we use to `translate3d` instead of `translateX` to be compatible with draggabilly
 - Added drag support to the annotationViewer template
 - Added reverse binding (with debounce) to annotationViewer controller
 - removed repeat/seek-to-start button
 - added additional reverse binding loop checks to ensure extra seeks are not done on the audio