I finally found some mingw64 libs for SDL
Toolchain files for cross-compiling for Windows (mingw64)
Removing old soft-oal files
openal-soft 1.15.1 binaries and headers for mingw-w64
OGG/Vorbis support on Windows!

Although x64 executable crashes, it has no relationship with the fact
that OGG/Vorbis compiles and links with it, on x86 is working like a
charm
Merge branch 'mingw64-zlib' of github.com:alericoveri/hecatomb into mingw64-zlib
Enabling HT_WITH_ZIP option
zlib 1.2.8 for Windows

Not tested yet
Enabling HT_WITH_ZIP option
zlib 1.2.8 for Windows

Not tested yet
Merge branch 'mingw64-zlib' of github.com:alericoveri/hecatomb into mingw64-zlib
Merge branch 'mingw64-zlib' into cross-mingw64

Conflicts:
	CMakeLists.txt