Note that the LinearSolverIstl class requires dune-common and
dune-grid to be installed in f.ex. /usr/local, but since the
cmake build support is experimental we add it for now.
- Only tested on a single workstation.
- Requires non-standard FindUmfPack.cmake module to be installed.
- Only builds library and spu_2p. No install or test targets.
- Lacks lots of include and flags statements for robustness.