[Feature] Remember code and dependency versions when generating atlas.

[alessandrofelder]

Is your feature request related to a problem? Please describe. If we discover a bug in an atlas years later, it may be hard to reproduce it, because the codebase and the dependencies will have moved on.

Describe the solution you'd like Should we keep track of the commit hash and dependency versions used to generate an atlas in the atlas metadata?

Describe alternatives you've considered None yet

Additional context n/a

[adamltyson]

Sounds like a v. good idea.

[adamltyson]

https://github.com/adamltyson/fancylog/blob/master/fancylog/tools/git.py