Display and refresh bus locations
Remove unused debug property
Display one bus at a time

Serialize a `selected` property that is set based on the student number
used for logging in. Give the Bus backbone model a `latLng` property
pointing to a `google.maps.LatLng` instance.
Use setInterval instead of setTimeout
Enable selecting which bus to view
Remove superfluous parentheses
Correct flash message key
Add cookie.js for managing cookies in JavaScript
Use unminified underscore.js and backbone.js

Easier to use for debugging
Remove old Backbone initialization
Consistent naming between server and client

Change `Bus` to `BusAssignment` and change `MapView` to reference
`currentAssignment` instead of `currentStudent`.
Remember selected assignment across page refresh
Remove unused backbone views and JST templates
Set time zone
Center map on currently selected bus
Update map center when selecting bus
Adjust map center
Correct bus assignment response factory
Fix buses_spec
Update session creation to use new form params