Clarify README gradle project vs app settings (#1264)
Clarify README gradle project vs app settings (#1264)

Update README to clarify which build.gradle lines to add to the project gradle file vs. the app gradle file
apollostack/apollo-android,apollographql/apollo-android,apollostack/apollo-android,apollostack/apollo-android,apollographql/apollo-android,apollographql/apollo-android