Use of Multiple Executors/ Clean Up

-Use Multiple Executors/ Simplify Logic
-Code formatting and clean up
-Removal of unused classes
There is one TODO in the SecondaryNameNodeExecutor for a subsequent patch to add a signal for the bootstrap.  
"// TODO add trigger for this event after other events have completed.  Remove sleep once this has been implemented."  The additional sleep is a temporary until the signal is implemented.  To make this clearer, I will put the sleep next to the TODO in the SecondaryNameExecutor.