Minor comments and documentation cleanup for sealvl ponds

[eclare108213]

• Short (1 sentence) summary of your PR:
  edit comments in code, fix doc grammar, remove whitespace

• Developer(s):
  @eclare108213

• Suggest PR reviewers from list in the column to the right.

• Please copy the PR test results link or provide a summary of testing completed below.
  ENTER INFORMATION HERE

• How much do the PR code changes differ from the unmodified code?

  • bit for bit
  • different at roundoff level
  • more substantial

• Does this PR create or have dependencies on CICE or any other models?

  • Yes
  • No

• Does this PR add any new test cases?

  • Yes
  • No

• Is the documentation being updated? ("Documentation" includes information on the wiki or in the .rst files from doc/source/, which are used to create the online technical docs at https://readthedocs.org/projects/cice-consortium-cice/.)

  • Yes
  • No, does the documentation need to be updated at a later time?
    • Yes
    • No

• Please document the changes in detail, including why the changes are made. This will become part of the PR commit log.

• removed superfluous 'w.e.' in comment

• edited coments regarding mpond, rdpnd

• edited documentation to improve grammar and remove white space

[eclare108213]

I can fix the parameter/namelist issue in this PR too, once we decide what to do.
@dabail10 @apcraig