Add a specific setup-level environment variable
When defining an environment variable for a language, you can define it at the specific setup level.
Environment variables set at the Specific level are stored in the setup defined by the GSTSETUPDIR environment variable. All configurations which specify the same GSTSETUPDIR will have these environment variables set. Specific-level environment variables will overrride those set at the Global level, but can be overridden by those set at the Project level.