Update Copyright year to 2021

[apcraig]

PR checklist

• Short (1 sentence) summary of your PR:
  Update Copyright year to 2021
• 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.
  Ran a quick suite on cheyenne again a prior baseline and everything compiled and ran, as expected. This should not affect any aspect of compilation.
• 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:

Also grepped for personal email addresses to change to cice-consortium at lanl dot gov but didn't find any in the repo.

[eclare108213]

@apcraig thanks for doing this. Which pdfs still need to be updated to 2021?