Use react-toolbox buttons. Added Cancel button for the entry editor.

src/actions/editor.js

@@ -1,8 +1,16 @@
+import history from '../routing/history';
+
 export const SWITCH_VISUAL_MODE = 'SWITCH_VISUAL_MODE';
 
 export function switchVisualMode(useVisualMode) {
   return {
     type: SWITCH_VISUAL_MODE,
-    payload: useVisualMode
+    payload: useVisualMode,
+  };
+}
+
+export function cancelEdit() {
+  return () => {
+    history.goBack();
   };
 }