Forum OpenACS Q&A: Patch to remove unnecessary topic_id and topic done

OK, https://openacs.org/sdm/one-patch.tcl?patch_id=41 removes the topic_id from URLs that point to individual messages, as well as topic.

I'm not going to attempt the zero stripping and filling idea, it saves so few chars anyway... but that shouldn't stop someone who really wants it from hacking it in and submitting the patch.

Note: this patch is tested a little on Q&A format bboards, and not tested at all on other formats of bboard.