core/utils.py:  Fixed a bug in valid_hostname() where it would cause breakage on certain versions of Python 3.  This should resolve the issue reported in pull request #428 (https://github.com/liftoff/GateOne/pull/428).
core/server.py:  Fixed an exception that could occur when checking origins if users connected to Gate One while it was still starting up (would just require the user reload the page but who wants to do that? =).
core/server.py:  Fixed a bug that was resulting in duplicated log lines for the root logger (gateone.log).
core/server.py:  Fixed a would-soon-be-a bug where an exception would be raised trying to figure out the remote client's IP address.  In Tornado 3.3 they changed it so that you can't use `self.request.connection.address[0]` to get the IP anymore.  Fortunately you can use `self.request.remote_ip` so it's an easy fix.
app_terminal.py:  Fixed a bug where Terminal commands would not show up under Python 3 if you had more than one.