Start adding python 3 support to pinball

Summary:
Run the safe futurize -1 fixers on all .py files

Use mysqlclient instead of MySQL-python:

'mysqlclient is a fork of MySQL-python. It adds Python 3 support and fixed many bugs.'
      https://pypi.python.org/pypi/mysqlclient
      https://phabricator.pinadmin.com/D246244

Reviewers: #python3, jon, ahaidrey

requirements.txt

@@ -5,7 +5,7 @@ django-sslify==0.2.7
 google_compute_engine==2.8.13
 guppy==0.1.10
 mock==0.8.0
-MySQL-python==1.2.3
+mysqlclient
 nose==1.3.4
 oauth2client==1.5.2
 pycryptodomex==3.7.2