Need to shorten the pathname for Ensemble packages

The pathname for Ensemble packages is very long. This causes problems with our build system on Windows when embedding the apps artifacts within other directories in the build hierarchy. This happens due to the fact that some tools still have a total pathname size of < 256 chars.

One of the path names that causes problems is:

Ensemble/src/com/javafx/experiments/ensemble2/samples/animation/timelines/TimelineEventsSample.java