Support for native Windows opa compilation: both compiler chain and adapted network layer using iocp.
[feature] build: support for Windows Mingw64 compiler chain
[feature] iocp: support for Windows IOCP networking
[fix] build: fixed linux compilation.
Some Windows specific code was not disabled when compiling on Linux.
[fix] iocp: reactivated file and UDP handling
This pull request has been merged (after some modifications). Big thanks to Stephan for his help!! (also expressed on the mailing list here: http://lists.owasp.org/pipermail/opa/2012-March/000865.html)