Pull bottom boundary from GCM #46
Description
PR #45 blocks initBTY and initATI from bday_mod.F90 from accessing all MPI processes. So a user must provide bathymetry as a file with the name <IHOP_fileroot>.bty
For most pkg/ihop applications a separate bathymetry file will result in better accuracy since the bottom interactions of ray paths occur at finer spacing than the GCM's horizontal cell centered spacing.