message: Changed to better error message for buyram
diff: @@ -122,8 +122,8 @@ namespace eosiosystem {
  int64_t bytes_out;
  - auto itr = _rammarket.find(S(4,RAMCORE));
  - _rammarket.modify( itr, 0, [&]( auto& es ) {
  + const auto& market = _rammarket.get(S(4,RAMCORE), "ram market does not exist");
  + _rammarket.modify( market, 0, [&]( auto& es ) {
  bytes_out = es.convert( quant_after_fee, S(0,RAM) ).amount;
  });
  