Upgrade trac to 1.0.1 and fix basic templates.
Don't hijack raw-attachments because the underlying on disk format
has changed to be kind of whack-a-doodle and apparently:

    "trac is better" - Alex Gaynor

Q.E.D.
Move around some directories and symlinks so that dump and restore
will continue to work post upgrade.
Merge in jonathanj's trac-0.12 template work.
Revert "Merge in jonathanj's trac-0.12 template work."

This reverts commit 12acf87492d5ce78faae440db399a14e0251ea56.
Pull in jonathanj's updated work.
enable builtin ticket deletion.
config changes
to don't
Better docstring than "potato"
I really hope we're done with this today, but if not, this will help the next victim^Wperson understand this.
Adjust install command to put symlink in the same place as the upgrade.
Merge pull request #10 from twisted-infra/upgrade-trac-1.0.1

Upgrade trac 1.0.1