Tripolar grid support on E/W boundaries

[marshallward]

Is your feature request related to a problem? Please describe.
We are attempting to run a simulation with the tripolar grid on the "east" (i.e. along the first-index boundary). This appears to be unsupported, and produces the following error:

FATAL: mpp_domains_define.inc(compute_overlaps_fold_east): when east boundary is folded, the domain must be symmetry for MOM_rot

#0  0xf5edaa in __mpp_mod_MOD_mpp_error_basic
	at /home/marshall.ward/gfdl/m6e/src/FMS2/mpp/include/mpp_util_mpi.inc:72
#1  0x1171367 in compute_overlaps_fold_east
	at /home/marshall.ward/gfdl/m6e/src/FMS2/mpp/include/mpp_domains_define.inc:4333
#2  0x1198deb in __mpp_domains_mod_MOD_mpp_define_domains2d
	at /home/marshall.ward/gfdl/m6e/src/FMS2/mpp/include/mpp_domains_define.inc:1061
#3  0x65644a in __mom_domain_infra_MOD_clone_md_to_d2d
	at /home/marshall.ward/gfdl/m6e/src/MOM6/config_src/infra/FMS1/MOM_domain_infra.F90:1746
#4  0x656e65 in __mom_domain_infra_MOD_clone_md_to_md
	at /home/marshall.ward/gfdl/m6e/src/MOM6/config_src/infra/FMS1/MOM_domain_infra.F90:1664
#5  0x439f7e in __mom_MOD_initialize_mom
	at /home/marshall.ward/gfdl/m6e/src/MOM6/src/core/MOM.F90:2924
#6  0xc6ea80 in __ocean_model_mod_MOD_ocean_model_init
	at /home/marshall.ward/gfdl/m6e/src/MOM6/config_src/drivers/FMS_cap/ocean_model_MOM.F90:290
#7  0xbe8a0c in coupler_init
	at /home/marshall.ward/gfdl/m6e/src/coupler/coupler_main.F90:1838
#8  0xbed0c9 in coupler_main
	at /home/marshall.ward/gfdl/m6e/src/coupler/coupler_main.F90:611
#9  0x4077ec in main
	at /home/marshall.ward/gfdl/m6e/src/coupler/coupler_main.F90:313

Describe the solution you'd like
We would like to see general support for (folded) tripolar grids along all index boundaries.

Describe alternatives you've considered
We are attempting to validate simulations across multiple configurations, so at the moment I cannot see any other solution other than to implement support for generalized tripolar support for all boundaries.