Squashed 'cmake/' changes from d1a7fd8..93da254

93da254 SlothAddTarget: simplified the code
33c4db6 SlothAddTarget: set policy CMP0022 to new
2d110d2 SlothAddTarget: exclude tests from all and add custom check target to build and run tests
139f4c9 SlothAddTarget: emulate interface libraries when not available
f0626f2 SlothAddTarget: bug fix populate private compile definitions

git-subtree-dir: cmake
git-subtree-split: 93da25470508ecaf304aeecf287bedb42b741c6e
Merge commit 'c76a16b756de0160cf51624da5e15b1c394dd574'