Here are some updated notes and code snippets for the following page:
https://www.contentful.com/developers/docs/android/tutorials/offline-persistence-with-vault/
The latest Android Gradle Plugin (3.0.1) has built-in support for annotation processors so the following code is not required and will result in an error if used:
classpath 'com.neenbedankt.gradle.plugins:android-apt:1.6'
apply plugin: 'com.neenbedankt.android-apt'
See android-apt documentation for more info:
https://bitbucket.org/hvisser/android-apt/wiki/Migration
The latest vault code for Gradle 3.0 is shown below:
annotationProcessor 'com.contentful.vault:compiler:3.0.1'
annotationProcessor 'com.contentful.vault:core:3.0.1'
compile 'com.contentful.vault:core:3.0.1'
For more info see Vault Git Documentation: