Major changes:
demos/ve/index.php
* Renamed ve-demo-content to ve-demo-editor
ve.init.mw.ViewPageTarget, ve.init.sa.Target
* Added handlers for dialog events
ve.ui.*Dialog.js
* Added skeleton classes for dialogs
ve.init.Target.js
* Create abstract class methods for Target.
ve.init.sa.Target.js
* Create Standalone target view methods.
ve.init.mw.Target.js
* Added MW specific target view methods.
* Integration action buttons are now added to the edit
view in the toolbar.
ve.Surface.js
* Simplified constructor, now requiring a target which contains the container
* Other changes include some documentation and code cleanup.
Bug: 39597
Change-Id: Iff39266bdd3052f34bda254ca407030dbbc81f26
