Make setting_default_level a specenum
Turn enum setting_default_level to a specenum, with names associated with each value. This will be needed when saving these values to the savegame as part of resolving https://www.hostedredmine.com/issues/692373
Turn enum setting_default_level to a specenum, with names associated with each value. This will be needed when saving these values to the savegame as part of resolving https://www.hostedredmine.com/issues/692373