Add ksno as a namelist parameter

[dabail10]

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PR checklist

• [X ] Short (1 sentence) summary of your PR:
  Add ksno as a namelist parameter. Addresses issue Add ksno namelist in icepack and cice #421
• Developer(s):
  dabail10 (David Bailey)
• 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.
  https://github.com/CICE-Consortium/Test-Results/wiki/31a1975df2.izumi.nag.20-04-10.154347.0
  https://github.com/CICE-Consortium/Test-Results/wiki/31a1975df2.izumi.intel.20-04-10.154347.0

All the compare tests are bfb on izumi. A number of tests fail on izumi because of timing out both in this branch and master.

• 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 Icepack 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/. A test build of the technical docs will be performed as part of the PR testing.)
  • Yes
  • No, does the documentation need to be updated at a later time?
    • Yes
    • No
• Please provide any additional information or relevant details below: