[CMake] enviroment variables (ice cream builds)

[Bill Hoffman]

On 6/19/2013 12:32 PM, Miller Henry wrote:
> Note that while we can possibly consider it a bug in my system setup
> that I need to set ICECC_CC and ICECC_CXX; but ICECC_VERSION is
> something the user needs to set.  Thus I really want cmake to make sure
> this variable is set the same as the first run of cmake.
CMake can not set environment variables for use during build time.   It 
expects a working compiler environment.  The cmake process is long gone 
by the time the native build tool is run.

-Bill