Updating the i2b2 Workbench to work with gitHub, newer Eclipse, and plugins

The i2b2 Workbench will be updated to work with newer versions of Eclipse as well as the way code is now packaged on gitHub. In addition, the "Features" ability in Eclipse is no longer supported. Therefore the i2b2 Workbench is being modified to work with "plugins" instead of features.

Also included in this Epic are some improvements to Temporal Queries and the Timeline views.