View nearby users

[richardverheyen]

View users who are 50m away by making a request to the API when you're logged in, submitting your lat and lng and getting back an array of User models (which never contain lat/lng)

AC: Never return lat/lng from third party users (set in users view)
AC: Only return users who are 50m away from the lat/lng which is submitted
AC: When you make the request again, user models locally get destroyed if they aren't in the new payload
AC: Users can only request nearby users once a minute (timeout applies from when you last received nearbys)