Remove check for git user.name and user.email in robotology-superbuild?

[traversaro]

Hello @robotology/everyone,
if you ever used the robotology-superbuild, you may have encountered the error:

 CMake Error at .build/_deps/ycm-src/modules/YCMEPHelper.cmake:326 (message):
  Failed to get git name.  Please set it with "git config --global user.name
  Firstname Lastname" or from your favorite git gui.
Call Stack (most recent call first):
  .build/_deps/ycm-src/modules/YCMEPHelper.cmake:1021 (_ycm_setup_git)
  cmake/BuildYCM.cmake:8 (ycm_ep_helper)
  .build/_deps/ycm-src/modules/FindOrBuildPackage.cmake:205 (include)
  cmake/BuildYARP.cmake:8 (find_or_build_package)
  .build/_deps/ycm-src/modules/FindOrBuildPackage.cmake:205 (include)
  cmake/RobotologySuperbuildLogic.cmake:68 (find_or_build_package)
  CMakeLists.txt:68 (include)

As this check is of limited use, my idea is to remove it in the next ycm-cmake-modules (and hence robotology-superbuild) release. If anyone has any other opinion, feel free to comment in robotology/ycm-cmake-modules#455 .