Save history of edits to database models

[tobiasmcnulty]

A/C:

• [ ] django-simple-history added to project + requirements file (see: https://django-simple-history.readthedocs.io/en/latest/quick_start.html#configure)
• [ ] history saved to the database for all models in the projects app, except PipelineRun
• [ ] admin integration workes (see https://django-simple-history.readthedocs.io/en/latest/admin.html for screenshots)