* clarify purpose of texrtti18 and texrtti19

tests/test/texrtti18.pp

@@ -2,6 +2,8 @@
 
 uses TypInfo;
 
+{ Check that the class RTTI does not have information about array properties }
+
 type
   {$RTTI EXPLICIT 
     FIELDS([vcPublic])

tests/test/texrtti19.pp

@@ -2,6 +2,8 @@
 
 uses TypInfo;
 
+{ Check that extended RTTI has information about array properties }
+
 type
   {$RTTI EXPLICIT 
     FIELDS([vcPublic])