Improved openshift --version, global flags, helpers

* Adding Docker and Go versions to the openshift --version command 
* Adding support to persistent (global) flags, openshift --verbose for now 
* Moved some code to external helper
Great, thanks for the comments! Most of all this is an exercise to understand the bits and how the project is organized. ;)
So the helpers package doesn't make sense at the same level of client and master, instead each client and master should have their own helpers (when it makes sense, maybe not yet)?