This enables CMake to create Makefiles targeting Windows CE devices.
CMake needs to be run within a cross compile command prompt and requires
a toolchain file which sets CMAKE_SYSTEM_NAME to "WindowsCE" and
optionally CMAKE_SYSTEM_VERSION.
In commit 485a940e (VS: Simplify MSVC version reporting, 2012-08-23) we
accidentally flipped the 0/1 values of MSVC_IDE. Flip them back and
teach the CheckCompilerRelatedVariables test to check the variable.
Remove the old-style "Windows-cl.cmake" and its helper "cl.cmake". Load
the information through new-style "Platform/Windows-MSVC-<lang>.cmake"
files. Factor information common to C and CXX into a helper file
"Platform/Windows-MSVC.cmake" loaded from the per-language files.
Patrick Gansterer
Brad King