fix wikimania pages like [[wm2006:Proceedings:LP1]]

The old https://wikimania2006.wikimedia.org/wiki/Proceedings:LP1 now appears at
https://wikimania2006.wikimedia.org/wiki/Internal:LP1

Old URL was broken in I51bfaada9c4f48610423156.

Change-Id: I1e9387f475670e1a9d780cd1af0fcbd53c2cd252