* Set the default option to hierarchical
* Add a new "hierarchical-folders" option which enables folders inside IDE's.
(cherry picked from commit bf773ccc417b47d01502c8151cea6188e33e16aa)
* It let ide's (like vs) display the source tree.
* Disabled by default.
* Soft requirement is cmake >= 2.8.12 .
* Offers 2 modes: flat & hierarchical.
* For detailed description see #14471
* Thanks @click for help and advises.
* Closes#14471
(cherry picked from commit c386711972260aa7b877cdc8cb49d24576ce1902)
Conflicts:
src/server/authserver/CMakeLists.txt