Add ability to color and label edges.

example.json

@@ -8,12 +8,12 @@
   ],
 
   "relationships": [
-    ["Sam", "Max", "solid"],
-    ["Sam", "Eve", "solid"],
-    ["Max", "Eve", "solid"],
-    ["Sam", "Bob", "solid"],
-    ["Alice", "Bob", "dashed"],
-    ["Alice", "Charles", "solid"],
-    ["Charles", "Max", "dashed"]
+    {"members": ["Sam", "Max"]},
+    {"members": ["Sam", "Eve"], "color": "red"},
+    {"members": ["Max", "Eve"], "label": "friends+"},
+    {"members": ["Sam", "Bob"], "color": "yellow", "label": "cuddle friends"},
+    {"members": ["Alice", "Bob"], "style": "dashed"},
+    {"members": ["Alice", "Charles"]},
+    {"members": ["Charles", "Max"]}
   ]
 }