GZigZag Benchmarking module

This module contains various pieces of code that test relative speeds
of various operations. The point is

1) provide a good basic intuition of what is fast and slow in Java,
    for purpose of choosing implementation methods

2) provide a test for different JVM's efficiency on different tasks
    (there are surprising diffrences here)

3) provide a testbed for zigzag algorithms and possible extensions,
    such as the constraint model where the feasibility from a speed
    perspective can be studied without building the whole system.


