Reduced severity of borders (which are a visual debugging aid)
Added new integration test to ensure MultiList panels are sized properly

This is a regression test for a fix that was committed on Friday.

This commit also introduces a new factory method for DefaultPlaceRequest
that can parse requests in the form PlaceId?param1=val1&param2=val2 ...
This was lifted from the annotation processing logic for @WorkbenchPanel.
It might come in useful for more stuff in the future.
Added clickable navigation to the default perspective. Makes interactive testing sessions easier.
New convenience method for adding parts to panel definitions
Fix for occasional comodification error (if panels rearrange children while def'n is being materialized)
Configuration for Infinitest IDE plugin: don't run the integration tests continuously!!!111!
Fixed drag-and-drop IllegalStateException on drop

The fix itself is a one-liner: PanelManagerImpl's overloaded addPanel() method was calling
setParent() on the new PanelDefinition it created. Parent-child management is now done only
by the parents themselves, as a side effect of addChildPanel().

The rest of the changes are an integration test for Drag-and-drop and minor modifications to
the framework to promote (Selenium) testability.