Python-engineio

- not necessary to hold the packet queue when upgrading ([commit](https://github.com/miguelgrinberg/python-engineio/commit/330c6b9379afb4a098c24456f1a96fed8c314b10))
- add link to stack overflow for questions ([commit](https://github.com/miguelgrinberg/python-engineio/commit/138fb60a9bb8a4aae86e08a5fd5485563733b9d1))
- pep8 fixes for previous commit ([commit](https://github.com/miguelgrinberg/python-engineio/commit/0c15cdc29ff130dba2887f5bfc2623f57b4fb45c))
- Use the correct text type for upgrade probes in both Python 2 and 3 [101](https://github.com/miguelgrinberg/python-engineio/issues/101) [#265](https://github.com/miguelgrinberg/python-engineio/issues/265). ([commit](https://github.com/miguelgrinberg/python-engineio/commit/4f0b4ea83298701a2e192c1e42fc3e917f1ee989)) (thanks **Sam Brightman**!)

- Pass cookies to websocket connection creation ([commit](https://github.com/miguelgrinberg/python-engineio/commit/c4c9178951aa2b9ede3ccec9af79324444e09314)) (thanks **Adrien Gavignet**!)
- close the aiohttp client to prevent exit warnings ([commit](https://github.com/miguelgrinberg/python-engineio/commit/9f6db446034a579415ae17dc0490ba23d92c723d))
- readme fixes ([commit](https://github.com/miguelgrinberg/python-engineio/commit/d6a33d22cfd3ebe8b4d78cd5c27607de837d16e9))

- exit service task if event loop is closed ([commit](https://github.com/miguelgrinberg/python-engineio/commit/ee6e00d5d4131f1d120797528b94140c2006b848))
- more tornado fixes ([commit](https://github.com/miguelgrinberg/python-engineio/commit/68ca0c2f3ebe2d255449a1f3a8b1b11d2deb84ef))

- added missing await in tornado driver ([commit](https://github.com/miguelgrinberg/python-engineio/commit/4ac92d4642f248ae763493c1d26e9e5f2058ac93))

- check for origin in Tornado's WebSocket handler ([commit](https://github.com/miguelgrinberg/python-engineio/commit/c4b506a0eb91a67e68944c8048ca9a867407c182))

- replace urllib3 with requests to get cookie support ([commit](https://github.com/miguelgrinberg/python-engineio/commit/41b8e29e49560170e852df1c5c070c6d311452d5))