* 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 c386711972)
Conflicts:
src/server/authserver/CMakeLists.txt
