We changed semantics so that each host only has one active event per
uuid.  That means that, on commit, we no longer care about the uuid of
endpoint's that handled data, and instead only care about host uuids
that handled data.
Updated code so that there is only one of an event per host: use host uuids more than local uuids.  Additionally, changed endpoint constructor so that user does not pass in host_uuid directly.  Instead, using host_uuid from ralph_globals object.
Endpoint constructor no longer takes in host_uuid argument, using ralph_globals to store that instead.
Endpoints no longer explicitly take in host_uuids in their constructors and instead use the ralph globals object.
Upated emit tests: endpoint no longer takes in the host uuid in its constructor, relying instead on RalphGlobals' host_uuid.
Minor cleanup: moved java_lib_tests to their own folder to clean up base directory of java_lib_test.
There wasn't rally a good reason for requiring variables to keep track of the host's uuid directly.