update android instructions to reflect newer react-native versions
update android instructions to reflect newer react-native versions

fix #25

luggit/react-native-config,luggit/react-native-config,luggit/react-native-config,luggg/react-native-config,luggit/react-native-config,luggit/react-native-config,luggit/react-native-config,luggg/react-native-config,luggg/react-native-config