Lots of cleanup

Questions slides are just h1.s now.
Indented code blocks appropriately.
Formatting tweaks.
Removed IRB line numbering in examples.
More formatting fixes
Skipping Duck Typing
Renamed a section
More cleanup.  Moved RSpec to day 4.
Added blocks and iterators slides
Added slides on docs
Added summary slides
Added RubyGems slides
Bumped Exceptions