Delete OLD pages.

There are a few pages in the OLD namespace such as HTML, CSS, and JS. They
seem to have made the top of the stats last month [1].

We should first make sure that OLD pages aren't indexed by search engines.

Second since the new top level pages for these have no issues shouldn't we
remove these pages from this OLD namespace?

-Garbee

[1] http://docs.webplatform.org/wiki/Special:Statistics