Fix multiline strings with single quotes in Cephelapod and implement both types in Kalypso, one new test should pass for both

stdlib/string.krak

@@ -181,5 +181,8 @@ obj string (Object, Serializable) {
         out.add(current)
         return out
     }
+    fun for_each(func: fun(char):void) {
+        data.for_each(func)
+    }
 };