Fix parsing of .quality, .alarm, .normal properties

src/formula_grammar.h

@@ -191,7 +191,7 @@ struct formula_grammar : public grammar<formula_grammar>
             	=	(alnum_p | '.' | '_' | '-' | '+')				//any alpha numeric char plus '.', '_', '-'
             	;
             symbol_attr
-            	=	(alnum_p | '_' | '.')								//any alpha numeric char plus '_', '.' for attribute names
+            	=	(alnum_p | '_' | '.') - str_p(".normal") - str_p(".alarm") - str_p(".quality")		//any alpha numeric char plus '_', '.' for attribute names
             	;
             //------------------------------ALARM NAME--------------------------------------	
             name