CMake is a strange and complex language for buildsystems,
and as such we need to let the main CMakeLists.txt be as
clear as possible.
Moving a bunch of code that deals with finding git via
default CMake way or pkg_cofig to a file named 'HandleFindGit'
on our cmake/Modules folder.
Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>
