Python-engineio-v3

- Support for gevent and threading in addition to eventlet. Also improved example application. ([commit](https://github.com/miguelgrinberg/python-engineio/commit/e72e4883a7301b8dc4bc1128597191d167776331))

- ensure all HTTP response payloads are returned as bytes ([commit](https://github.com/miguelgrinberg/python-engineio/commit/d38d57f6af139a02adeb5e73f8a3308542ffc3a7))
- Added robustness when dealing with disconnected clients ([commit](https://github.com/miguelgrinberg/python-engineio/commit/7b39dbb6c547ed9dde19f4537e6b3f8e725a4fb6))
- removed assert_called_once from tests ([commit](https://github.com/miguelgrinberg/python-engineio/commit/e6f1b8b7f6c5acb1f37f595cd9696bc5d855c987))
- Added logging for websocket upgrade ([commit](https://github.com/miguelgrinberg/python-engineio/commit/4b5cecab56f4891040f7da04ced523ea50cb8dca))
- Fixed incorrect unit test ([commit](https://github.com/miguelgrinberg/python-engineio/commit/583736a3af266d15c31ee03546f11d018fb97e42))
- rename close() to disconnect() for consistency ([commit](https://github.com/miguelgrinberg/python-engineio/commit/12cc2830374a4848127614f1a21fe8712574219b))

- Switch README to rst format ([commit](https://github.com/miguelgrinberg/python-engineio/commit/4fb16f8574004ad5b846d81eb9a9d958b448a7da))
- minor documentation and code fixes ([commit](https://github.com/miguelgrinberg/python-engineio/commit/f0e6be6ce16e98f270327a516754ec4d18d7b2f1))

- Better support for unicode in Python 2 ([commit](https://github.com/miguelgrinberg/python-engineio/commit/9fb200cbf81992cc6cc1cf8f1c9fc15471e5f0f9))
- allow connect event handler to send data to client ([commit](https://github.com/miguelgrinberg/python-engineio/commit/a0dbf69fec47db0bfdca6585267eed21bfc2da91))

- Added non-decorator format for Server.on() ([commit](https://github.com/miguelgrinberg/python-engineio/commit/2d8d41c514f317e4c2e347030d82c351fbe0fb4e))
- declared vendered js file ([commit](https://github.com/miguelgrinberg/python-engineio/commit/584aba250334fe10949cefbbb99afff89222f024))
- Added pypy to travis builds ([commit](https://github.com/miguelgrinberg/python-engineio/commit/b982ed13d64ece4c76c6af323e2b29db4bdabfdf))
- minor documentation updates ([commit](https://github.com/miguelgrinberg/python-engineio/commit/a25b639ea3e833a28725fd22b36de5b5f6973744))
- Initial commit ([commit](https://github.com/miguelgrinberg/python-engineio/commit/4303b86e4f363e746957e6adecea303089e90f70))
- initial version ([commit](https://github.com/miguelgrinberg/python-engineio/commit/1d53a103ffcc43d1482fecb489d748c1ffaadbe0))