Binary wheels for windows

[zbynekwinkler]

Please consider providing binary wheels for windows. They can be auto built on appveyor. I was able to locally build current master for python 2.7 32bit by installing the "python compiler release" from Microsoft and using vcpkg-built libjpeg-turbo which is somewhat heavy weight. I also had to define snprintf to _snprintf to get it linked. I am not really sure it works yet.

[cbm755]

This sounds like a nice thing to build into future CI improvements.

I'd happily review such a change but I'm unsure how to start doing it myself: contributions welcome!