@Override
public RedisClient decrby(String key, long decrement, Handler<AsyncResult<Long>> handler) {
sendLong(DECRBY, toPayload(key, decrement), handler);
return this;
}
<BUG>@Override
public RedisClient del(List<String> keys, Handler<AsyncResult<Long>> handler) {
</BUG>
sendLong(DEL, toPayload(keys), handler);
return this;

@Override
public RedisClient append(String key, String value, Handler<AsyncResult<Long>> handler) {
sendLong(APPEND, toPayload(key, value), handler);
return this;
