Update to fix issue where drag image would never display due to $evalAsync being evaluated too late in the lifecycle. $apply is needed to tell the digest to run and update the default drag information with the new drag image.

Updated dragstart to have a drag handler (dragstartHandler), to match dragend's dragendHandler.
Merge pull request #107 from vandermore/fixForDragImageNotDisplaying

Update to fix issue where drag image would never display due to $evalAsy...