Better handling of mpi.
Better handling of mpi.

NicolasSchnitzler/dtk,d-tk/dtk,d-tk/dtk,NicolasSchnitzler/dtk,NicolasSchnitzler/dtk,d-tk/dtk,rdebroiz/dtk,NicolasSchnitzler/dtk,rdebroiz/dtk,d-tk/dtk,rdebroiz/dtk,d-tk/dtk,rdebroiz/dtk,d-tk/dtk