OZP-60: Initial dragndrop work

Copied Old drag and drop code and began porting
OZP-60: Finished initial port of widget-side drag-n-drop
OZP-60: Initial port of dragndrop container and base class
Merge branch 'master' into feature/ozp-60-dragndrop
OZP-60: Fixing build errors
Merge branch 'master' into feature/ozp-60-dragndrop
OZP-60: Dragndrop integration into widget API
OZP-60: Adding dragndrop to channel shouter
OZP-60: Fixed dragndrop init
OZP-60: Channel Listener initial dragndrop
OZP-60: Drag and Drop fixes
OZP-60: Dragndrop fix
OZP-60: Dragndrop improvements and fixes
Merge branch 'master' into feature/ozp-60-dragndrop
OZP-60: dragndrop firefox fixes
OZP-60: Switching dragndrop service names to constants
Merge branch 'master' into feature/ozp-60-dragndrop
OZP-60: Drag and drop appears to work in all browsers
OZP-60: dragndrop refactoring

Moving addCallback and addCallbacks to DragnDrop base, since that is where
the callbacks objects are defined

Creating fireCallbacks to encapsulate firing logic

Getting rid of getMouseCoordinates, since jquery already does the
equivalent normalization
OZP-60: DragnDropBase unit tests