Add descr attribute to JSON parser

src/Parser/PP.hs

@@ -164,7 +164,8 @@ data RecordPP = RecordPP {
         transitions :: [RecordTransition],
         initialStates :: [String],
         trueStates :: [String],
-        predicate :: Maybe (QuantFormula String)
+        predicate :: Maybe (QuantFormula String),
+	description :: Maybe String
 } deriving (Show)
 
 $(deriveJSON defaultOptions ''RecordTransition)