WIP Initial Commit for Frog13

Hacked markdown to add speaker notes instead of vertical nav; Added
diagrams to multiple slides
Cleaned up generally; added styled shapes/layouts for Frog history
Added some notes to the slides

Still WIP tho
Added proper support for notes within markdown files
Used new notes syntax
More content, styling refinements
Removed log from markdown plugin
Updated frog13 sass file
Updated frog13.css
Updated frog13 styles (again)
Line spacing
Notes restyle, don't have preview
Merge branch 'master' of github.com:adamhepton/reveal.js
Most up-to-date content, still incomplete *gulp*
Final content ...?
Removed extraneous Notes separator
Added 'final' class to last stage on progress bar
Use progress bar
Added styles for progress bar
Updated README