The grand Guice injection fixup

This branch will get all the Guice changes to make DI work correctly and eliminate all the race conditions and have the startup and shutdown of the service controlled by the dropwizard framework.

The first patch is fixing all the lazy injection places, add explicit injection for everything that is referenced through Guice and uses eager injection everywhere.
There are slave Singularity instances? Seems I do not fully understand the code yet. I assumed that there is a leader and a number of standby instances. If this code should only run on the leader, the simpler change would be to have runActionOnPoll to check for it being the leader and not execute the action accordingly. Otherwise, Singularity will need to deal with hooking / unhooking these tasks when the leadership changes.