CMake cleanup.
Removes old CMakeModules.
Squashed 'CMakeModules/' content from commit 1c4c56f

git-subtree-dir: CMakeModules
git-subtree-split: 1c4c56f7ed77f06e74692fe2ffa4ed4ec2294611
Merge commit 'deca10d295ebbc1502c9b752c23275447c80acd2' as 'CMakeModules'