Update to tech note section 2-14 MOSART

[nmizukami]

Description of changes

Minor corrections and editing.

1. manning equation was fixed,
2. added new line in two equations (eq number is 2.14.2).
3. added water abstraction via irrigation demand from land model in the water balance equation with short descriptions.

Specific notes

Contributors other than yourself, if any:

None

CTSM issues resolved or otherwise addressed, if any:

Resolve #3860

If answers are expected to change, describe (delete this line otherwise):

N/A

Any user interface changes (namelist or namelist defaults changes)?

N/A

Testing planned or performed, if any:

Built documentation on Casper (NCAR HPC) following the working with documentation guide, no errors.

Requirements before merge:

• I have followed the CTSM contribution guidelines.

[nmizukami]

One question is whether or not 2.14.5. Difference between CLM5.0 and CLM4.5 should be removed. Also should I mention flood?

[samsrabin]

Adding next: Needs assignee.

[swensosc]

These changes look fine. The only question I have is whether the new variable for irrigation should be 'I' instead of 'IR'.

[nmizukami]

Removed "2.14.5. Difference between CLM5.0 and CLM4.5" section and changed IR to I for symbol for water abstraction from irrigation (based on Sean's comment).

[slevis-lmwg]

@nmizukami looks like you addressed Sean's review, so I'm approving.