Foursquare Checkin Filter
- Display foursquare auth errors
- Redirect after getting code out of auth redirect query string
- Refactor foursquare code to be more OO and separate auth from API calls
- Refactor checkin cache to store checkins rather than API response (could cause issues with merge venues, etc.)
- Update checkin storage by making one API call and using since date filter (or one call every 10 min)
- Update form and layout to be nicer
- More filter options
- Add checkin with information