Add some comments to gremlin-driver Client.
Merge remote-tracking branch 'origin/master'
Merge remote-tracking branch 'origin/master'
Get basic load balancing strategy for gremlin-driver.

Simply implemented round-robin right now, but made sure that hosts were being marked as dead when connections failed to be made to the specified host.  Also prevented failure of any one host from preventing a client from being created.
Add todo for later thought.