.config/rss2email.cfg: Add Peter Stuge's blog

He posted "Making nginx serve git-http-backend and gitweb on the same
URL" for me :), so I should see what other interesting nuggets come
out ;).
.config/rss2email.cfg: Add comment feed for Titus' blog
.config/rss2email.cfg: Add Olympia/Tacoma news and job feeds
.gitconfig: Add `authors` alias for `shortlog -se`

I hardly ever use `shortlog`, so I don't remember which options give
me the concise list of project authors.  For some reason, I seem to be
the one maintaining .mailmap files in a number of projects, and this
command helps identify inconsistent IDs.
.config/rss2email.cfg: Add a bunch of new feeds

Mostly for jobs and journals.