Shared access spack configuration

Looking at these examples from other HPC centres, it might be this could be done much more concisely, but it might require the modules to set the correct environment variables

e.g.

    netcdf:
        buildable: false
        modules:
            netcdf@4.4.1.1.6%gcc+parallel-netcdf+mpi:   cray-netcdf-hdf5parallel/4.4.1.1.6
            netcdf@4.4.1.1.6%intel+parallel-netcdf+mpi: cray-netcdf-hdf5parallel/4.4.1.1.6
            netcdf@4.4.1.1.6%cce+parallel-netcdf+mpi:   cray-netcdf-hdf5parallel/4.4.1.1.6
            netcdf@4.6.1.3%gcc+parallel-netcdf+mpi:     cray-netcdf-hdf5parallel/4.6.1.3
            netcdf@4.6.1.3%intel+parallel-netcdf+mpi:   cray-netcdf-hdf5parallel/4.6.1.3
            netcdf@4.6.1.3%cce+parallel-netcdf+mpi:     cray-netcdf-hdf5parallel/4.6.1.3
            netcdf@4.4.1.1.6%gcc~parallel-netcdf~mpi:   cray-netcdf/4.4.1.1.6
            netcdf@4.4.1.1.6%intel~parallel-netcdf~mpi: cray-netcdf/4.4.1.1.6
            netcdf@4.4.1.1.6%cce~parallel-netcdf~mpi:   cray-netcdf/4.4.1.1.6
            netcdf@4.6.1.3%gcc~parallel-netcdf~mpi:     cray-netcdf/4.6.1.3
            netcdf@4.6.1.3%intel~parallel-netcdf~mpi:   cray-netcdf/4.6.1.3
            netcdf@4.6.1.3%cce~parallel-netcdf~mpi:     cray-netcdf/4.6.1.3
    netcdf-fortran:
        buildable: false
        modules:
            netcdf-fortran@4.4.1.1.6%intel: cray-netcdf-hdf5parallel/4.4.1.1.6
            netcdf-fortran@4.4.1.1.6%cce:   cray-netcdf-hdf5parallel/4.4.1.1.6
            netcdf-fortran@4.4.1.1.6%gcc:   cray-netcdf-hdf5parallel/4.4.1.1.6
            netcdf-fortran@4.6.1.3%intel:   cray-netcdf-hdf5parallel/4.6.1.3
            netcdf-fortran@4.6.1.3%cce:     cray-netcdf-hdf5parallel/4.6.1.3
            netcdf-fortran@4.6.1.3%gcc:     cray-netcdf-hdf5parallel/4.6.1.3