Feature/private bins

- [ ] Ready to merge - closes #982
- [x] Db update scripts for private column
- [x] Db query templates for checking privacy
- [x] Model methods, delegating to store
- [x] `app.param('bin')` to check privacy of bin
- [ ] method to test if user can see bin
- [ ] UI for setting a bin to private
- [ ] Db query for setting private on bin