Fix performance of Counter destructor by using appropriate containers in Sink

This was developed on top of !1439 (merged) and thus should only be merged after it.

The problem was due to the use of deque, extremely slow for deleting when getting big. The code was written that way supposing we would get ~100 entities (aka some human readable quantity), but we seem to reach > 100000... So deque has been replaced by a map with entity's memory address as a key, and now the deletion is fast