[FIX] The .over class for droppables is now correctly removed
[FIX] Links are now moveable again in JointJS
[NPE]
[FEATURE] New JointJS.add/removeCustomClass
[FEATURE] console.log / .error are now forwarded to Java and get forwarded to the log4j Logger (debug resp. error)
[NPE]
[FIX] Drag'n'Drop actions now also work if the drop area has child dom elements
[FEATURE] JointJS can now have a default selection (if the selectionConverters convert null to an non-null value)
[NPE]
[LOG] New ExecUtils.logException methods to log an eventually thrown exception of a Future
[LOG] The Future returned by ExecUtils now displays its return value / thrown exception in the debugger
[LOG] Reduced log level to info for aborted browser loading due to disposal
[UI] Fancy lines paper background for JointJS
[FIX] When a scripts runs at a moment the browser was already disposed null was returned. Now a ScriptExecutionException is thrown.
[FIX] No more SWTException by ClipboardListener
[FIX] ExecUtils.async now really runs async

Before it executed the callable directly if the callers was already in the UI thread.
This leads to a problem if the callers willingly wanted the UI queue to empty first all actions.
[NPE]
[REFACTOR] Moved out modification notification functionality of Composer
[API] JointJS now can notify observers about changes made
Revert "[FIX] ExecUtils.async now really runs async"

This reverts commit b23491d55c22b07e30d8326ce800c68b9e7a2390.