Renamed health_monitor gem to bosh-monitor

Signed-off-by: Jeffrey Peckham <peckham@pivotallabs.com>
Renamed director gem to bosh-director

Signed-off-by: Jeffrey Peckham <peckham@pivotallabs.com>
Namespace bosh-director executables to bosh-director-*

Signed-off-by: Rob Day-Reynolds <rdayreynolds@pivotallabs.com>