New compset naming conventions for CAM7

Compset naming conventions need to be expanded for the upcoming CAM7

Proposal:

F{W}{C}{LT|MT}{scenario}{Slim}

F will include new prognostic greenhouse gases (This will replace the specified chemistry option)
W if is a WACCM run
C if is a full chemistry run
LT for low top or MT for mid top
LT = 58 levels currently, initial condition files, tau_0_ubc=false + other tunings if needed later
MT = 93 levels currently, initial condition files, tau_0_ubc=true + other tunings if needed later
scenario = HIST, 1850, 2000Climo, etc.
Slim - Indicates SLIM Land model if appropriate

The compsets F2000Climo, FHIST and F1850 will be deprecated as the 32 level will not be supported

Examples:
FMTHIST will be mid top historical
FCLTHIST will be full chemistry low top historical
FWC2000Climo will be WACCM with chemisty in a 2000 climo scenario
FLT2000ClimoSlim will be low top 2000 climo scenario with CTSM SLIM model

### Is there anyone in particular you want to be part of this conversation?

@cecilehannay @JulioTBacmeister

### Will this change (regression test) answers?

No

### Will you be implementing this enhancement yourself?

Yes, but I will need some help