Disable buttons based on available_actions instead of hiding them.

Added _controls partial as provider specific partial.
This is because available actions are used for disabling the buttons instead of hiding them.
To display only buttons that are available for provider, I had to create provider specific partials.
All transition states are wm_pemding now, wm_penging has no actions available (all buttons disabled), added restoring_state in ovirt to wm_pending
Set the wm_state in controller to change state to pending (transition) then api call is sent and response sets the wm_state pending in view and disables the buttons. Removed setting transition state in js controller.
Disable buttons after one of them is clicked, set wm_state to PENDING on click to display pending right away
Updated translations
Merge pull request #218 from jtomasek/states_polishing

States polishing
Merge pull request #221 from tzumainn/master

Add additional provider-specific tests