Merge remote-tracking branch 'upstream/master'

Conflicts:
	index.html
	js/reveal.min.js
Add new markup examples (new full screen features)
Update README.md
Merge pull request #2 from clairecoloma/patch-1

Update README.md
Merge remote-tracking branch 'upstream/master'

Conflicts:
	Gruntfile.js
	README.md
	index.html
	js/reveal.min.js
Merge remote-tracking branch 'upstream/master'

Conflicts:
	index.html
Add a different index.html page and add instructions
Greatly improved the default theme! :metal:
Minor formatting
Add example of avatar style image
Add example of avatar style heading
Add example of JoliCode prez
control slide visibility through class instead of style
basic flexbox styles
merge dev into flexbox
use flexbox to vertically center slides
merge dev into flexbox
fall back on js centering when flexbox is not supported
postmessage plugin is now part of reveal.js core
bubble all reveal.js events to parent window through postMessage