Addresses O'Reilly copyedits for preface

- Adds a line about additional contributions, setting to wip while
I find out how many lines we can add at this stage. Also the
acknowledgements section has been removed from the O'Reilly edition
so I'm tracking that down.

Change-Id: I852c883d6696e9dcdcd843d6039247cb533f014f
Merge "Addresses O'Reilly copyedits for preface"