fix the ford fulkerson example edge bug

Author: chen0040

examples/example-ford-fulkerson.html

@@ -73,6 +73,7 @@ <h2>MaxFlow-MinCut (Ford-Fulkerson)</h2>
                     for(var i = 0; i < adj_v.length; ++i) {
                         var e = adj_v[i];
                         var w = e.other(v);
+                        if(w != e.to()) continue;
                         if(e.highlighted) continue;
                         g_edges.push({
                             from: v,

test/ford-fulkerson-spec.js

@@ -20,6 +20,9 @@ describe('MaxFlow-MinCut', function(){
         g.addEdge(new jsgraphs.FlowEdge(6, 2, 6));
         g.addEdge(new jsgraphs.FlowEdge(6, 7, 10)); 
 
+        g.node(2).label = 'Hello';
+        g.edge(0, 1).label = 'World';
+       
         var source = 0;
         var target = 7;
         var ff = new jsgraphs.FordFulkerson(g, source, target);