Fixes for Windows

[retep998]

[therustmonk]

@rbranson Merge it, please, because I can't compile some libraries clean without this fixes. I've test it.

[retep998]

@DenisKolodin There are alternative libraries that offer similar functionality but are up to date, such as https://github.com/danburkert/memmap-rs

[therustmonk]

@retep998 Thank you for memmap-rs, great lib, useful for me! But there is a dependency in lib: https://github.com/rustcc/coroutine-rs/ I have to twist own forks to fix it. The best way to use an alternative to coroutine-rs, I know, and I've found https://github.com/zonyitoo/coroutine-rs which looks alive, no mmap deps and based on fork of coroutine-rs, but another version differs in implementation without backward compatibility. Maybe I whimper, dependency hell is not so large with Cargo )