added mpi typedefs for cusp csr matrices in new file mpi_projection.h
added mpi typedefs for cusp csr matrices in new file mpi_projection.h

feltor-dev/feltor,feltor-dev/feltor,mwiesenberger/feltor,mwiesenberger/feltor,mwiesenberger/feltor,feltor-dev/feltor,feltor-dev/feltor,mwiesenberger/feltor