Change auto reloader enviroment varible name to SANIC_SERVER_RUNNING
Fix some typo mistakes, flake uncompatibilities and such problems.
Raise NotImplementedError for operating systems except posix systems for auto reloading.
Fixed error where KeepAliveTimeout wasn't being triggered in the test suite, when using uvloop
Fixed test cases when using other asyncio loops such as uvloop
Fixed Flake8 linting errors