[CMake] cleaning targets

[Tyler Roscoe]

On Thu, Nov 06, 2008 at 12:57:52PM -0500, Michael Jackson wrote:
> Are you using a dedicated build directory or are you running cmake  
> directly from your source directory? If the latter.. STOP.. don't do  
> that. If you use a dedicated build directory then cleaning up from  
> cmake is as simple as rm -rf Build/ and there are no worries about  
> adding to source control because none of the build products are within  
> your source directories. Does this make sense?

I have everything in a build/ subdirectory, but that includes
CMakeLists.txt (I'm trying to keep the root of all my projects as clean
as possible, with source in src/ and utility scripts in util/ and all
the build stuff in build/).

tyler