MOM6: Merge branch 'wfcooke-user/wfc/grid_initialization' into dev/gfdl

- New diagnostics added to available_diags

- NOAA-GFDL/MOM6@db9555f Merge branch 'wfcooke-user/wfc/grid_initialization' into dev/gfdl
- NOAA-GFDL/MOM6@95bc47b Replace FATALs/WARNINGs for modified channel widths
- NOAA-GFDL/MOM6@4686129 Merge branch 'user/wfc/grid_initialization' of https://github.com/wfcooke/MOM6 into wfcooke-user/wfc/grid_initialization
- NOAA-GFDL/MOM6@1686e12 Corrected indexing of vars array.
- NOAA-GFDL/MOM6@51ab273 Reverted writing of dx_cv and dy_cu to ocean_geometry as they are there as dxCvo and dyCuo. Make available for output via register_status_field call.
- NOAA-GFDL/MOM6@5e3697c Adds output of Channel narrowing info to screen and dy_Cu and dx_Cv to geometry file.

ocean_only/global_ALE/layer/available_diags.000000

@@ -91,6 +91,12 @@
 "ocean_model", "dyCv" [Unused]
  ! long_name: Delta(y) at v points (meter)
  ! units: m
+"ocean_model", "dyCuo" [Unused]
+ ! long_name: Open meridional grid spacing at u points (meter)
+ ! units: m
+"ocean_model", "dxCvo" [Unused]
+ ! long_name: Open zonal grid spacing at v points (meter)
+ ! units: m
 "ocean_model", "area_t_percent" [Unused]
  ! long_name: Percentage of cell area covered by ocean
  ! units: %

ocean_only/global_ALE/z/available_diags.000000

@@ -91,6 +91,12 @@
 "ocean_model", "dyCv" [Unused]
  ! long_name: Delta(y) at v points (meter)
  ! units: m
+"ocean_model", "dyCuo" [Unused]
+ ! long_name: Open meridional grid spacing at u points (meter)
+ ! units: m
+"ocean_model", "dxCvo" [Unused]
+ ! long_name: Open zonal grid spacing at v points (meter)
+ ! units: m
 "ocean_model", "area_t_percent" [Unused]
  ! long_name: Percentage of cell area covered by ocean
  ! units: %