Improvements to the Debtags web editor

The Debtags web editor can now give random tips.

It's a simple addition, but it now makes many things possible:

If you do a lot of tagging work and happen to conceive some useful tip, please send it to the mailing list and I'll add it to the tips page.

I also tried to tidy up the interface of the web editor as much as I could, but I have mixed feelings about it. Help us out: make a draft HTML-only prototype of how the interface could be improved, and send it to me or the list.