[CMake] Submitting patches to rely on external libraries for certain platforms

[Matt Rogers]

Hi,

Would the CMake developers be interested in patches that allows people to use 
their already installed libraries such as curl, expat, libtar, etc. on 
certain platforms and fallback to the in-source libraries if they're not 
installed?

Initially, I think this would be great for unix/linux based platforms that 
generally come with these libraries already installed or very easily 
available and then can be extended out into the windows world later (when I 
have information on how to actually do it?

Thanks
--
Matt