CI: disable 'install' because it is not used at teh moment. It should be re-enabled when 'install' targets will be set in all the sub-packages.

Put a toplevel makefile.  Since all of the subdirectories do not work at this point, only two of them are referenced in the toplevel CMakeLists.txt

Fix compiliation problem by explicitly adding Eigen3 to the CMakeLists.txt file; however shouldnt Eigen3 be automatically included via GeoModelKernel??

This reverts commit 3a4fa222.

This example is updated to create materials which have actual elements; otherwise database is unreadable