Disable check-in if user is already checked-in AND event has not passed.
Display link to check in if user is within 30 meters of event
Begins to create an AJAX request to rails sending in coordinates and doing logic in server rather than in JS
Successfully returns user's data if user is in the area
Adds user to view when ajax returns success, and alerts user if they are not within vicinity
Fixes show page to display follow link properly
Uses faye/private_pub to update the page if user is nearby
Sets up private_pub to listen to faye server on Heroku