Update to grazing logic.

[rosiealice]

Prevents crops etc. being grazed to death in the off-season, per NorESMhub/CTSM#202

Description:

Collaborators:

Expectation of Answer Changes:

Checklist:

• My change requires a change to the documentation.
• I have updated the in-code documentation .AND. (the technical note .OR. the wiki) accordingly.
• I have read the CONTRIBUTING document.
• FATES PASS/FAIL regression tests were run
• If answers were expected to change, evaluation was performed and provided

Test Results:

CTSM (or) E3SM (specify which) test hash-tag:

CTSM (or) E3SM (specify which) baseline hash-tag:

FATES baseline hash-tag:

Test Output:

[rosiealice]

I just realized this has a bunch of parameter file changes wrapped in accidentally. I will remove them now.