Add gencost to Case format
Created by: espenol
Added gencost to Case so that it is loaded and stored there, added gencost for the test (power) systems in the repository and added a simple test to verify that a value in gencost is loaded correctly.
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Created by: espenol
Added gencost to Case so that it is loaded and stored there, added gencost for the test (power) systems in the repository and added a simple test to verify that a value in gencost is loaded correctly.