Fix the "got non-string for process arg" errors resulting from blank config lines.
Add logfile as a config option and fix several bugs in the log.py.

 * Fixed bugs due to several log functions attempting to use
   "config.advanced.debug" and "config.basic.logfile". These are both located
   under the config.main section.
 * Add LICENSE header and encoding specification to log.py. (Yes, we need
   these.)
 * Add log.warn() function back in.
Add file headers  and cleanup module docstring in oonib/runner.py.
Cleanup log/print statements and docstrings in oonib/runner.py.
Create a tempdir at the top of the repo directory for tor_datadir if not set.
Use the socks_port option from oonib.conf when starting Tor.
Don't pass the tor_binary option to txtorcon if not set.

 * txtorcon will handle finding the tor binary for us.
Update the .gitignore.
Add script for killing the TravisCI spawned oonib after thirty seconds.

 * ∃!isisⒶwintermute:~/code/torproject/ooni-backend ∴ date
   Sun Apr 21 07:25:24 UTC 2013
   ∃!isisⒶwintermute:~/code/torproject/ooni-backend ∴ travis-lint
   Hooray, /home/isis/code/torproject/ooni-backend/.travis.yml seems to be solid!