fix-plugin-issues

Honeslty I'm pretty embarrased by the state of affairs for our provisioning client right now. The code is unwieldy and error prone.
The tests are mainly a joke. All this change is doing is essentially fixing funcitonality that was broken when it was initially released.
The funtionality being fixed is allowing for a class or module determine what values to return for a field and the ability to do string
interpolation on a series of fields.

If this code is unacceptable that is fine, but IMO that means doing a complete re-write of the socialcast-command-line gem. I'm willing
to attempt that, but this functionality is needed for a customer as outlined at https://vmware-com.socialcast.com/messages/17526939?ref=group