Merge pull request #1 from sharplet/master

Complete Chapter 4 exercises
5.1 Adding some structure
5.2 Sass and the asset pipeline
Use ruby 1.9.3-p374 (rbenv)
5.3.3 Named routes
5.3.4 Pretty RSpec
5.4 User signup: A first step
Merge pull request #2 from sharplet/filling-in-layout

Complete up to section 5.5
Add terminal-notifier-guard to bundle
Merge pull request #3 from sharplet/guard-notifications

Add terminal-notifier-guard to bundle (for test suite notifications)