Add video & details to Ep 03 README

Author: brettchalupa

episode-03/README.md

@@ -1,10 +1,21 @@
 # Test Driven RSpec - Episode 03, Configuring RSpec
 
-[Watch the screencast on YouTube.](https://www.youtube.com/watch?v=)
+[Watch the screencast on YouTube.](https://www.youtube.com/watch?v=mHPKEdgLirA)
 
 The completed code from Episode 03. This episode covers configuring
 RSpec for use with Ruby on Rails.
 
+This episode goes into detail on:
+
+- The `.rspec` file
+- `spec/spec_helper.rb`, its various options, and when to require it
+- RSpec `spec/examples.txt` and using `--only-failures`
+- RSpec output formats
+- RSpec slow test profiling options
+- RSpec test seed and its importance
+- `spec/rails_helper.rb`, its various options, and when to require it
+- Requiring and including `spec/support/` code in specs
+
 Install the dependencies `bundle install` and run the specs with `bin/rspec`.
 
 Software used: