The benchmark reaches the end time after 129 time step.

Adding media description and using constant density property
where possible. In other cases refer to the existing parameter.

And replace AddTest calls to OgsTest in cmake.

* input new files about slope stability

* input document of slope stability

* add something in Test file

* some changes in test file

* some changes in test file

* some changes in test and prj file

* some changes in input files

* [T/MCAS] Relax nonlinear solver tols. Formatting.

* [T] Reformatting file.

* Add somethings in input files

* some changes in slope files

* Cleanup. Set ctest to fail.

Co-authored-by: tengfei <dengtenfei2016@hotmail.com>
Co-authored-by: Dmitri Naumov <github@naumov.de>