Support Bubble integration tests.
There are no real changes to Bubble yet, but there are now some failing unit tests.
Bah, didn't mean to commit this yet.
Added integ/unit tests for show and hide, added some visibility indicators to bubbles (for testing)
Merge branch 'bubbleTooltip' of https://github.com/ReadyTalk/swt-bling into bubbleTooltip
Merge branch 'bubbleTooltip' into linkdableEffect