Reverts PR #1440
Reverts PR #1440

There's a dependency conflict between zappa for python-dateutils (requiring 2.7.0) and botocore's python-dateutil (requires <2.7.0)
Miserlou/Zappa,Miserlou/Zappa,pjz/Zappa,scoates/Zappa,pjz/Zappa,scoates/Zappa