objects-classes: splitting out some ch1 content into ch2

Author: getify

objects-classes/README.md

@@ -9,4 +9,5 @@
 * [Foreword](foreword.md) (by TBA)
 * [Preface](../preface.md)
 * [Chapter 1: Object Foundations](ch1.md)
+* [Chapter 2: How Objects Work](ch2.md)
 * TODO