message: Fix serialisation of rdctype::str to always NULL-terminate
diff: @@ -506,9 +506,10 @@ public:
  }
  else
  {
  - create_array_uninit(el, sz);
  + create_array_uninit(el, sz + 1);
  for(int32_t i = 0; i < sz; i++)
  Serialise("", el.elems[i]);
  + el.elems[sz] = 0;
  }
  }
  