OC-22 - Initial implementation

    This adds a Segment menu which contains the same items as the
    context menus for segment and LQI manipulation.
OC-22 - Refactoring to use guava EventBus

    This pulls the new (in OC-22) Segment menu out into its own
    class and uses an EventBus to bind things together.  This will
    help reduce some of the dependencies in the UI components.
OC-22 Additional eventbus migration
OC-22: Additional EventBus migration, and fix a bug with reset target
Restore row selection after a target edit has been committed
Refactor Segment-related events, and other cleanups