supporting same languages as highlight.js
First implem for adding classes to enclosing elts.

Extra text representing classes is detected and correctly removed.
Adding attributes isn't working yet.
Uses the right method setAttribute.

Works better, and the html elements get their attributes.
Add attributes extracted from an attribute.

Allows to add attributes to element of an attribute which contains
the attribute pattern.
Cleanup code, remove console log debugs.
Add 'data-element-attributes' attr. to 'section'.

By default '{\\\.\s*?([^}]+?)}'.
Add unit-tests for attributes in mardown elements.

Test paragraphs, list items and img attributes.
don't autoplay videos in notes window #624
Merge branch 'classes_in_markdown' of https://github.com/VonC/reveal.js into dev
format tweaks markdown.js, remove extra image asset
documentation for #677
don't transition between identical backgrounds
fix edge case in background transitions (closes #604)
Added slide numbers options and the css files updated as well.

the *.min.js didn't chaged yet.
move the slide-number out of the controls to a proper position and little fix to the updating event.
synthetic fix
change SlidesNumber position and start page counter at 0 instead 1
generate background hash under additional conditions
add convex background transition
add concave and zoom background transitions