- cleaning of pkg/matrix (fix multi-tiles and multi-threaded). - exp. matrix_example tested with MPI and multi-threaded.
- cleaning of pkg/matrix (fix multi-tiles and multi-threaded).
- exp. matrix_example tested with MPI and multi-threaded.

altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h