Add git commit when content changes are made

[DinisCruz]

This will allow the use of Git to track changes made to files

The idea is that everytime the save button is used, a git commit with those changes is made (after that we need to figure out a way to push those changes to the git server, so that there is an auto-backup of the data saved)

Until there are logged in users, the changes will be made using a generic bsimm-bot account

Will be interesting to see if there can be race-conditions on multiple users triggering an save at the same time