keeping track of software version

[samleenz]

Something I need to think about: how to keep track of what software versions / specific commands were run for an analysis project at a point in time?

Ideally the code in this repo will be pretty stable, but having some way to record the commit hash for each module used would be useful potentially. E.g., so when we write a paper in two years time it is easy to say we ran version x of tool y with parameters foo and bar.