Extras for file browsing,
Few changes need to be made for file browsing.
first of all always display files, if there's errors show warning and redirect to '/' of that revision.
secondly prev/next buttons need to show current branch(and tag ?) (double check for git)
another great feature would be a checkbox 'stay at branch' then each next/prev would walk only at that branch I think we might put this into vcs cs methods.