Slightly better error message for fromJSON

Author: Inkrementator

source/iopipe/json/serialize.d

@@ -727,6 +727,7 @@ void deserializeImpl(P, T, JT)(ref P policy, ref JT tokenizer, ref T item) if (i
         item = T.fromJSON(tokenizer);
     } else {
         // This will fail to compile. Try to nudge the user to use a policy
+        pragma(msg, "Hint: fromJSON also doesn't compile with parameters (JSONTokenizer, ReleasePolicy) or  or just with (JSONTokenizer)");
         item = T.fromJSON(tokenizer, policy);
     }
 }