waitCount ignores already decoded futures #143
Description
Current implementation of waitCount deliberately ignores already decoded but not obtained by user futures and waits only for non-received from Tarantool yet. It's weird because user doesn't actually differentiate between them since some futures can be decoded under the hood during any of wait* methods. If he needs to wait only for non-received from Tarantool futures, he could use waitCount with conn.getFutureCount + count argument.
Firstly, we should decide whether to change the behavior now without having proper versioning.