Merge pull request #17 from effrafax/master

Improved testcases and minor modifications for multiproject builds
Added simple tooltip to dependency nodes
Fixes to style
Support showing tasks for multiprojects
Revert "Support showing tasks for multiprojects"

This reverts commit e30c4d3b3bf1e32c742b60d8937aaaf6989a4619.
Show path rather than task name to diff between subprojects in gradle multiprojects
Add zoom in/out capability with keyboard for graph