* Add --submit, -s: for submitting code and marking the code as submitted
* Add --discard to allow discarding from the CLI
* Add 'def submit(self, server, changenum, files):' function to all SCMClients
** Add functionality for subversion (I don't have time right now to hunt down
   all the supported SCMs and patch for them).
*** Includes the Review URL, bug list, reviewers, approvers and description
    in the message sent to subversion.
* Add close(): to aid in closing a review
* Add get_review_url(): centralize code to collect this information
** Point users of this code to the function
* Add get_approvers(): List of people who have clicked 'ship it'
* Add get_reviewers(): List of people who have submitted reviews
* Add get_description(): Get the description held by reviewboard
* Add get_bugs(): List the bugs tagged with this review