Last UG updates

[grantfirl]

• Add info regarding UFS comparison data for UFS_case_gen
• Fix merge problem from previous PR (chap_quick)
• Use optional -fm and -vm arguments in UFS_case_gen examples

Output: https://ccpp-scm-grantfirl.readthedocs.io/en/latest/index.html

[grantfirl]

@scrasmussen @mkavulich @lulinxue I forgot who was going to work on the batch/mpi documentation. That can go into this branch too.

[lulinxue]

@scrasmussen @mkavulich @lulinxue I forgot who was going to work on the batch/mpi documentation. That can go into this branch too.

I recalled that Tracy @hertneky would work on batch related document and probably Soren @scrasmussen would work on mpi document. Please correct me if I am wrong.