Modified rbt post to append current local branch to the POST request, modified the rbt status to obtain the saved local branch from the GET request, and altered the formatting of rbt status to show the last local branch that was used to post the review request.

I tested both rbt post and rbt status manually.
rbt post

Create branches in both git and bzr repos and do rbt post and ensure that local_branch is added to the review request as extra_data
Create bookmark in hg repo and do rbt post and ensure that local_bookmark is added to the review request as extra_data
Do an rbt post in and hg repo without specifying a bookmark and ensure that no local_bookmark is not added to the review request as extra data
Do an rbt post with an SCM that doesn't have branching/bookmarking capabilities (I used svn) and ensure no unintended extra_data is being added

rbt status

Run rbt status in repos that support branching (both git and bzr) and ensure that only the 'Branch' column shows up
Run rbt status in repos that support branching (hg) and ensure that only the 'Bookmark' column shows up
Run rbt status in a repo that don't support branching/bookmarking (I used svn) and ensure that neither 'Branch' nor 'Bookmark' columns show up
Run rbt status --all and ensure that both the 'Branch' and 'Bookmark' columns show up, and also that each branch and bookmark shows up properly associated with the correct review request
Make terminal large enough to fit each record of the rbt status output in one line and ensure that it outputs properly
Shrink terminal small enough to require word wraps for various records in the rbt status output and ensure that it outputs properly