CMake Nightly Date Stamp
properly detect processor architecture on Windows

CMake is usually run as a 32 bit process even on 64 bit Windows, so the
PROCESSOR_ARCHITECTURE environment variable would always return x86. This post
gives a description on how to do it properly:

http://blogs.msdn.com/b/david.wang/archive/2006/03/26/howto-detect-process-bitness.aspx
Merge topic 'Win-HOST_SYSTEM_PROCESSOR' into next

add8d22 properly detect processor architecture on Windows
e597ba2 CMake Nightly Date Stamp