ve.Editor

Objectives:

* Split ve.Surface into ve.Editor and ve.ui.Surface
* Move actions, triggers and commands to ve.ui
* Move toolbar wrapping, floating, shadow and actions functionality to configurable options of ve.ui.Toolbar
* Make ve.ce.Surface and ve.ui.Surface inherit ve.Element and use this.$$ for iframe friendliness
* Make the toolbar separately initialized so it's possible to have a surface without one, as well as control where the toolbar is

Some change notes:

VisualEditor.php
* Added standalone module for mediawiki integrated unit testing

ve.ce.Surface.js
* Remove requirement to pass in an attached container to construct object
* Inherit ve.Element and use this.$$ instead of $
* Make getSelectionRect iframe friendly
* Move most of the initialize stuff to a new initialize method to be called after the surface is attached to the DOM

ve.init.mw.ViewPageTarget.js
* Merge toolbar functions into setup/teardown methods
* Add toolbar manually (since it's not added by the surface anymore)

ve.init.sa.Target.js
* Update new init procedure for editor, surface and toolbar separately
* Move toolbar floating stuff to ve.Toolbar

Change-Id: If91a9d6e76a8be8d1b5a2566394765a37d29a8a7