Keep known-good ANTLR version in repository (wikitext, 85a0852)

I've had a fair bit of trouble getting things back up and running with the move to ANTLR 3.0.1, so I'm going to store a known-good version of ANTLR (source archive plus patches) in the repository. This may be paranoid but I don't won't to get caught out in the future.

Signed-off-by: Greg Hurrell <greg@hurrell.net>