[plt-scheme] trac spam (and other things)

spam:

I've added a mandatory field with no default to the trac bug report
submissions (that is filled in by drscheme when you submit that way),
so hopefully that'll cut down on the bug report spam we've been
getting.


email notifications:

I also enabled trac email notifications, but didn't add everyone's
password in to their trac accounts. I wanted to, but couldn't quite
figure out how to do iit and then it occurred to me that people might
just be happy not to get notifications. I'm not sure it is a good
idea, but for now you'll have to enter your email address into trac
yourself if you want to get emails about your tickets.


planet.plt-scheme.org page speedup:

the front page was computing the top bug closers on each page load
which seems to be quite expensive once you get about ... 20 tickets.
Sigh. I didn't see a way to speed that up, so the top bug closers list
is only recomputed hourly now.

Robby