title: How do we get list of users within range of certain city?
body: <p>I have list of users with field city. How do we get list of users who are about 200km from certain city?</p>
  
  <p>I am using geocoder gem to find nearest location. However, how do we do it through city only without lat and lon present on the db for User?</p>
  
  <pre><code>user = User.last    
  user.address = 'Sydney'
  location = Geocoder.search(user.address).first
  lat = location.latitude
  lon = location.longitude
  
  within_user = SpreeUser.near([lat, lon], 200, units: :km)
  </code></pre>
  
  <p>This will give the error because latitude and longitude does not exist for User. Is there a way it can be done through other field, like address in this case?</p>