Make it work with newer React-Native versions.

I think we shouldn't set a hard coded constrain here. Instead we should document it in the readme with which version it is tested and working?

android/build.gradle

@@ -16,5 +16,5 @@ android {
 }
 
 dependencies {
-    compile 'com.facebook.react:react-native:0.37.+'
+    compile 'com.facebook.react:react-native:+'
 }