Work Progress - May 29 - Jun 1

Fix the drag-and-drop of the existing Core (http://www.rpi.edu/~laut/GG/app.jnlp).

• Pressing the codelet in the codelet template window on the left does NOT duplicate codelet in a different position.
• Releasing the codelet in the middle scriptlet window drops the codelet to the exact vertical position where it is dropped.
• The drop line now indicates where the top of the dragged codelet collapses with the codelets in the middle scriptlet window.

TODO: The current scriptlet window displays the script of at most one event at one time. To allow the scriptlet window to show the scripts of more than one event at the same time, a considerable rewrite of the scriptlet window is needed.