"mssh" command naming

[Lestropie]

Don't know how much thought has previously gone into the command naming convention for those commands that operate on multi-shell SH data. I do recall that with initial implementation of MSMT there were some ms* commands, but functionalities were later integrated into more generic commands.

Would referring to such data as "shard" be inappropriate; ie. is that term being reserved specifically for the act of decomposition, rather than multi-shell spherical harmonics data?