Add floediam, hfrzazilmin namelist and Update Icepack

[apcraig]

For detailed information about submitting Pull Requests (PRs) to the CICE-Consortium,
please refer to: https://github.com/CICE-Consortium/About-Us/wiki/Resource-Index#information-for-developers

PR checklist

• Short (1 sentence) summary of your PR:
  Add floediam, hfrzazilmin namelist and Update Icepack
• Developer(s):
  apcraig
• 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.
  Full test suite run on cheyenne with 3 compilers, all tests pass. Some results are bit-for-bit, some are not due to changes in Icepack. https://github.com/CICE-Consortium/Test-Results/wiki/cice_by_hash_forks#3a90f39ca315b1a51a45000db10d64ff62ffaf93
• How much do the PR code changes differ from the unmodified code?
  • bit for bit
  • different at roundoff level
  • more substantial, non bit-for-bit changes coming in with Icepack
• Does this PR create or have dependencies on Icepack or any other models?
  • Yes, requires an updated version of Icepack
  • 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:

Add floediam and hfrazilmin as CICE namelist. Requires latest
version of Icepack. Update documentation.

Addresses #472.

Icepack has two non bit-for-bit changes including

• a fix to multiple declarations of floeshape (Moved floediam and hfrazilmin to icepack_parameters Icepack#342)
• a fix to the convergence scheme in icepack_atmo (Add ustar_prev to while loop in icepack_atmo Icepack#341)