Add OOJS v1.0.5 to core

Just adding code for now, not actually used for anything yet outside
of extensions.

Note that OOJS does not work in older browsers and will
actually cause JS errors when loaded in browsers that don't support
ES5. We'll resolve this by adding an ES5 shim later.

Change-Id: Ifea6405c24778486bb9b310398b82ffb28ddbfcd
Merge "Add OOJS v1.0.5 to core"