RTGOV-57 Refactored service analytics model to retain the merged definitions at each level, and changed the color selector mechanism to be based on analysing severity, with the mapping to colour performed in the svg generator.
Make the severity analyzer MVEL script configurable via overlord-rtgov properties.
Update the approach used by the default severity analyzer mvel script to use the history and summary metric information. Provide config property to enable user to provide their own alternative script.