Inserting into queue is slow when queue is long

[Marian Bäuerle]

Inserting into the queue is slow when the queue is long. This is already recognizable when the queue has about 10,000 items.

This has mainly to do with the implementation of the queue. Adding items at the end of a list takes siginficant time (I think O(n^2)), because it has to reverse the list twice to update it.
By replacing the implementation with Erlang :queue the performance can be improved by about 100 times.
I ran a quick test with benchfella and got this result:

benchmark name	iterations	average time
Comparison stack	5000	648.01 µs/op
Erlang queue	1000	2301.37 µs/op
Que queue	10	188906.30 µs/op
Improved Que queue	500	3484.63 µs/op

Edit: This is the bench script