Add check in code model
Add check in model
Set up relationships between check_in, check_in_code, and user
Annotate models
Add rotues for check in codes
Add link to check in codes for admins
Add check in codes controller with basic blank methods
Add blank views for check in codes
Index view for check in codes
Form for creating check in codes
Add link to check in code and show view
Add list of users and count of users
Add enabled to check in codes
Add route for checking in
Add class methods for the current active code
Add enabled/disable actions and add check in form to home page
Actually add check in form to the home page
Add check ins controller with create method
Move check in below main background
Give ability to check in to any signed in user