[CMake] Project-level CLRSupport option

[Matthew Bentham]

Hi all,

Please could someone have a quick look at the patch I've attached to issue 8808:

 http://www.cmake.org/Bug/view.php?id=8808

The idea is to set CLRSupport at the project level when the compile flags require it.  This is needed to make certain sorts of linking work in VS2010 and currently there's no other way to set it from CMake.

All the best,

Matthew Bentham
ArtVPS