A few additions for the sea ice.

[dabail10]

Description of changes:

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• Added new seaice_key.ipynb which is a start to the sea ice key metrics.
• modified the list of variables for the seaice notebook to make it faster. There is a new cice_vars_full.yml list
• updated the sea ice runs in config.yml
• changed the color table
• fixed the options for the cluster
• to do: configure the config.yml for sea ice in the key_metrics directory