feat(edges): click handler

src/EdgeRenderer/Edge.js

@@ -13,6 +13,7 @@ export default (props) => {
     <path
       className="react-graph__edge"
       d={`M ${sourceX},${sourceY}L ${targetX},${targetY}`}
+      onClick={e => console.log('on edge click')}
     />
   );
 };

src/style.css

@@ -38,13 +38,18 @@
 }
 
 .react-graph__edges {
+  position: absolute;
+  top: 0;
+  left: 0;
   pointer-events: none;
+  z-index: 2;
 }
 
 .react-graph__edge {
   fill: none;
   stroke: #333;
   stroke-width: 2;
+  pointer-events: all;
 }
 
 .react-graph__nodes {