Removed file filter in support of the existing include/exclude filter keys; the latter also providing more flexibility. Relates to https://github.com/playframework/playframework/issues/2662#issuecomment-40549091

A scripted test is now also provided covering a few scenarios and providing a nice template to devise plugins from.
Merge pull request #3 from huntc/task-includes-excludes

Includes/Excludes filtering for plugins