Allow gerrit approve to post comments on closed changes

The web UI permits comments on closed changes, so we should do the
same thing with the SSH based approve command.  However like the
web we need to ignore the vote flags if its closed, as those cannot
be changed.

Bug: issue 488
Change-Id: I366b41785eea27b939f44ea2c2613a8d67a57001
Signed-off-by: Shawn O. Pearce <sop@google.com>
1 file changed