Some changes for Win32 cross compiling. It still compiles fine under Linux
too of course. Hopefully I've tracked down any of the niggley issues with
compiling on the other platforms before I merge.
Merge remote-tracking branch 'upstream/master' into 2013june/winbuild
Don't warn about being double+ included anymore
Merge pull request #587 from monkeyiq/2013june/winbuild

2013june/winbuild