Docs on Sea Ice Diagnostics (#234)

Co-authored-by: Spencer Wong <88933912+blimlim@users.noreply.github.com>

Author: anton-seaice

.gitignore

@@ -7,4 +7,5 @@ __pycache__
 .DS_Store
 ._*
 .vscode
-.pytest_cache
+.pytest_cache
+.ipynb_checkpoints