[CMake] INCLUDE_DIRECTORIES and UNIX style separated environment variables

[Bill Hoffman]

Bill Hoffman wrote:
>
>>>
>> Hmm, I see, good point.
>>
>> The thing is that I started to use it like this since I have 64bit 
>> and 32bit systems and couldn't figure out how to distinct that for 
>> the CMakeLists.txt, because depending on the ARCH libs and includes 
>> are differently. But it's true, using the env is error prone.
>> ___
CMAKE_SIZEOF_VOID_P  should be 8 on the 64 bit system if that helps.

-Bill