Provide mw-redirect and mw-disambig classes for links on the surface

To mimic PHP parser, or, in the case of mw-disambig, what I would want
the PHP parser to be.

Change-Id: I70dc426a3b87daef27816d6d86130c39f30ba0f4
Merge "Provide mw-redirect and mw-disambig classes for links on the surface"