BackblazeB2 support
Features
- Support BackblazeB2 for files storage
- Support BackblazeB2 for json database
Improvements
- Slack uses direct storage url when possible (i.e. it immediately sends users to the url of the file on backblaze servers instead of asking this app to redirect users to backblaze)
- Add in-memory cache layer
- Setup continuous integration (CircleCI) with "linting", "unit testing" and "e2e testing" tasks
- Add Heroku install documentation