[platform-debug-dev] Variable support moved to Debug UI

[Jared Burns <jared-eclipse@xxxxxxxxx>]

I just released changes that move the launch configuration variable support 
from ExternalTools UI to Debug UI. The work is in a functional, but not 
polished state - it all seems to work, but I plan to go through and rename 
some classes, change some strings, etc.

If you have the org.eclipse.ant.ui, org.eclipse.debug.ui, or 
org.eclipse.ui.externaltools project checked out in your workspace, you'll 
need to check out *all* of these projects in order to get a clean compile.

- Jared