Create context instance in surface.
Move over getSelectionRect into ce.surface
Cleanup ve.surface contstructor class
Move linmod/html test objects to sandbox.js
Change-Id: I0cf602ef991100bf6128c68750b02a00566911dc
Switch sandbox demo to use new ui modules
Update VisualEditor.php to use ve2 modules
SpecialPageSandbox working
Change-Id: I8261d6bf6ceb6ae7b7bfa5f61aec6a0121906765