Remove disposed Bubbles from the Registry.
This was what was causing the WidgetDisposed error described in #42.
Remove @Ignore from XVFB failing integTest.
This was fixed by #42 and closes #27.
Merge pull request #55 from l1m5/master

Remove unnecessary ON_TOP style.
Merge pull request #56 from l1m5/master

Add SWT.TOOL to PopOverShell (adds DropShadow).