CHANGELOG.md

*   Add code of conduct to contributing guide

    *Jon Moss*

*   New section in Configuring: Configuring Active Job

    *Eliot Sykes*

*   New section in Active Record Association Basics: Single Table Inheritance

    *Andrey Nering*

*   New section in Active Record Querying: Understanding The Method Chaining

    *Andrey Nering*

*   New section in Configuring: Search Engines Indexing

    *Andrey Nering*

Please check [4-2-stable](https://github.com/rails/rails/blob/4-2-stable/guides/CHANGELOG.md) for previous changes.