Insert notes from 'JavaScript: The Good Parts' about augmenting types.
Merge branch 'sandbox'
Merge branch 'sandbox'
Merge branch 'sandbox'
Merge branch 'sandbox'
Merge branch 'sandbox'
Merge branch 'sandbox'
Merge branch 'sandbox'
Merge branch 'sandbox'
Merge branch 'sandbox'
Fix merge conflict in Inheritance.
Update gemfile.