RB Close

Allows the user to submit a command 'rb close <rid>' to mark a review request as either 'discarded' or 'submitted'.

On local dev server, tried several combinations of the command and viewed the review request to ensure it match what was desired by the command.

Working cases:
rb close <rid> 
rb close <rid> --description='some desc'
rb close <rid> --type='submitted' 
rb close <rid> --type='submitted' --description='some desc'
rb close <rid> --type='discarded' 
rb close <rid> --type='discarded' --description='some desc'

Bad input cases:
rb close <bad rid>
rb close <rid> --type='bad type' 

Retested with rb-general changes (removal of extra options)