[mpi3-coll] Missing reduce_local and reduce_scatter_block in create_op text

Hi Torsten, There are a few lists that are missing MPI_REDUCE_LOCAL and MPI_REDUCE_SCATTER_BLOCK. 1) Section 5.9.2 List of predefined ops missing MPI_REDUCE_LOCAL, MPI_ALLREDUCE_SCATTER_BLOCK, and all non-blocking variants. 2) Description for MPI_OP_CREATE missing MPI_REDUCE_LOCAL, MPI_REDUCE_SCATTER_BLOCK, and all non-blocking variants. I guess we may not need to list the non-blocking variants in this list, but we should definitely add REDUCE_LOCAL and REDUCE_SCATTER_BLOCK. -Adam