Consistent shader order for qsb

Currently when qbs (QShaderBaker) creates the baked shader, the shader variants are in random order.

What I would like is:

> qsb [constant parameters] -o shader.frag.qsb shader.frag
> qsb [constant parameters] -o shader2.frag.qsb shader.frag
> diff shader2.frag.qsb shader.frag.qsb
-> prints nothing

Reasoning:

• When the qsb files the are in git, it would be good to see when they actually change even when you re-bake the shaders, have some automatic baking script etc. And even though qsb files are small, keep git changes at minimum.
• When someone has updated .qsb file and you want to see what changed, qsb dump both version and compare easily.
• Similarly if you get .frag.qsb and .qsb files and want to know if second was actually created with the first, bake, dump and diff.