More Conan packages moved to CPM (2nd try)
Replaces !3458 (closed).
Packages still on Conan:
- PETSc (no CMake build system)
- LIS (no CMake build system)
- tfel (upstream MGIS requires tfel to be installed)
- Qt (no CMake build system, Qt 6 is CMake-based)
- netcdf-cxx (requires netcdf-c, proj4, haven't done yet) -> will be added later
- vtk -> will be added later
- Check if libs are picked up from system (Eigen, Boost, hdf5, LibXml2?, VTK)
- Check for new warnings
- Feature description was added to the changelog
- Tests covering your feature were added?