Update versions of vaadin-board and vaadin-charts (#4)

bower.json

@@ -18,8 +18,8 @@
     "tests"
   ],
   "dependencies": {
-    "vaadin-board": "1.1.0-alpha1",
-    "vaadin-charts": "6.0.0-alpha2",
+    "vaadin-board": "1.1.0-beta1",
+    "vaadin-charts": "6.0.0-alpha4",
     "vaadin-core": "10.0.0-alpha7"
   }
 }