mkdir module to replace system(...) call from fortran

bringing PETSc and svLS back to the master

Finally, we have all solvers in one branch, Compressible (Native/PETSc), Incompressible (leslib,svLS). Note CmakeLists.txt needed to set shared libs to no after PETSc set it to yes and fouled link.

This one builds

new files or files that moved from one directory to another in merge