fix(package): update react-native-vector-icons to version 6.4.1

Closes #51

Author: greenkeeper[bot]

package.json

@@ -19,7 +19,7 @@
     "react-native-fetch-blob": "0.10.8",
     "react-native-image-resizer": "1.0.0",
     "react-native-modal": "2.5.0",
-    "react-native-vector-icons": "4.6.0",
+    "react-native-vector-icons": "6.4.1",
     "react-navigation": "1.0.0-beta.11",
     "realm": "1.10.3"
   },