anchor.diff:  RETURN *
   ----
   
  ---2. Create a point layer. This can be done using the neo4j-spatial procedure `addLayer`:
  -
  -----
  -CALL spatial.addLayer("locations","SimplePoint","")
  -----
  -
  ---3. Add the nodes to the point layer. The following cypher will add all the nodes with the `Location` label to the point layer:
  -
  -----
  -MATCH (l:Location)
  -WHERE NOT (l)<-[:RTREE_REFERENCE]-()
  -WITH collect(l) AS locations
  -CALL spatial.addNodes('locations', locations) YIELD node
  -RETURN count(*)
  -----
  -
   --4. Validate you can perform a query that calculates the distance between two location nodes. 
   
   ----
  
positive.code: 
  
  ////
  .Configuration
  . Optional, remove comments from squid.conf, `grep -Eiv '(^#|^$)' /etc/squid/squid.conf > /etc/squid/squid.conf.new`
  . Set `http_port` from `3128` to `80 accel allow-direct`. This will allow Squid to proxy all HTTP traffic.
  
negative.code: RETURN a.name, b.name, toInt(distance(point(a),point(b)) / 1000) as distance;
  ----
  
  This query will provide the distance in kilometers between two locations which are in the same country:
  
  ----
  MATCH (a:Location {name: "Baltimore"}),(b:Location),(a)-[:WITHIN]->(c:Country)
  