Prettify: converted to using single init element

1. Plugin now uses a `.wb-prettify` element as initialization
   point.  All settings are configured from CSS classes and/or
   data attributes on this element.
2. Updated to use new 4.0 plugin template.
Prettify: updated demos

1. Updated to match change to how plugin now uses a single
   `.wb-prettify` element to initialize.
2. Ported French demo from v3.1.
Merge pull request #3200 from patheard/prettify

Prettify: converted to using single init element
Prettify: Minor cleanup to better align with new plugin template
Merge pull request #3208 from pjackson28/cleanupprettify

Prettify: Minor cleanup to better align with new plugin template
fixed window start to have the timer start immediately after polyfills are loaded
Corrected spacing issues with addition to vapour.js
Implemented global approach to assigning focus to an element.
Merge pull request #3210 from wet-boew/hotfix-vapour

fixed window start to have the timer start immediately after polyfills a...
Merge pull request #3209 from pjackson28/globalfocus

Implemented global approach to assigning focus to an element.
Cleaned up indentation of vapour.js
Merge pull request #3212 from pjackson28/cleanupvapour

Cleaned up indentation of vapour.js
Build: add CSS transitions to Modernizr build
Session: updated English demo, added French demo
Session: added modal dialog for timeout warning

1. Modal built using Magnific Popup and exposes logic via
   `modal.wb-session-timeout` event.
2. Countdown of reaction time displayed in modal.  Once zero
   is reached, session expired message and "Sign in" button displayed.
Merge pull request #3213 from patheard/session-timeout

Session timeout modal dialog
Datalist polyfill: Aligned polyfill with v4.0 model for plugins
Merge pull request #3211 from pjackson28/datalistrewrite

Datalist polyfill: Aligned polyfill with v4.0 model for plugins
Realigned JS files with jQuery style guide.
Merge pull request #3214 from pjackson28/alignwithjquerystyleguide

Realigned JS files with jQuery style guide.