Birdback/distillery — pull request #5 by malthe (2014-09-15 12:47:23+00:00)
Title: Build fixture in order of creation

That is, we increase a global counter every time the 'Set' class
is subclassed.

The effect is that within a given fixture set, subsets are created
in the order of class creation.

Previously, the order was unpredictable.