#12
The path of the img that is now returned is:
/resources/graphs/1378123450430.png, so the full path in my case is
http://cassandra.iti.gr:8443/cassandra/resources/graphs/1378123450430.png

(this is valid only for newly created graphs and clusterings

Also the "img" was added on the following requests :
    GET /cassandra/api/scn?prj_id="prj_id" (to get the csn graph image)
    GET /cassandra/api/scnclusters?graph_id = "graph_id"
    PUT /cassandra/api/scnclusters