Allow override of HTML escaping in code blocks

This way, authors can use HTML for special formatting.

add missing theme readme

merge in timer in notes window, timer now stays hidden until initial …

…time is set

fixed issue with dependency loader failing when there were 0 async sc…

…ripts (hakimel#214)

remove sharing code for sample presentation

clean up initialization, conditionally load classList polyfill prior …

…to reveal.js

comments, tweaks and a new slide highlighting mobile support

better example of state usage

readme history update

Merge pull request hakimel#5 from matthewlein/master

contenteditable and arrow keys