stop using queue

[xmcp]

queue is designed for multithreading uses and acquire a lock in every method call. in a word, it's really slow.

just use list instead. it's much (about 50x) faster.

>>> import timeit
>>> timeit.timeit('q.put(123)', 'import queue; q=queue.Queue()', number=10**6)
24.48412793993996
>>> timeit.timeit('q.append(123)', 'q=[]', number=10**6)
0.5576901608900329

[jeffswt]

Since this class had been recently removed due to a potential rewrite, I will take this suggestion into consideration with the utmost importance.

I personally believe that writing a class (not thread-safe) by myself would be a better option.