Use setuptools if available
Fix miscalculation of struct sizes in Windows

Fixes #92
Re-enabled Poll tests on Windows
Updated documentation for TCP.open and UDP.open
Clarify docs for TCP.simultaneous_accepts
Preemptively fix compilation if Visual Studio 2012 is used

libuv doesn't support it yet, but it will at some point
Use git reset instead of checkout for picking the right libuv revision
Raised libuv revision
Set version and updated changelog
Updated sample tox.ini file
Fixed classifier