Implement cluster update, tweak spark master url handling
Implement cluster update, tweak spark master url handling

tmckayus/oshinko-cli,radanalyticsio/oshinko-cli,radanalyticsio/oshinko-cli,tmckayus/oshinko-cli,tmckayus/oshinko-cli,radanalyticsio/oshinko-cli,crobby/oshinko-cli,crobby/oshinko-cli,crobby/oshinko-cli