Trying to make a stable base class for the JobManagerImplementation for other implementations to extend from and save themelves some effort
Modifying inaccurate class description
More refactoring to make the code reusable. Added initial cut at PrestoJobManagerImpl.
Trying to fix bug
Another shot at fixing the no command id bug
Merge branch 'presto' into develop

Conflicts:
	genie-web/src/test/python/jobs/genie2pigtest.py
Fixing inconsistency between the parameter passed from UI and the one accepted by the server for cluster name and cluster id for jobs