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.
Scheduled maintenance will be performed on April 24th between 22:00-02:00. There will also be unstability with object storage on April 22nd between 22:00-00:00
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.