Merge in jonathanj's trac-0.12 work.
Revert "Merge in jonathanj's trac-0.12 work."

This reverts commit 93a1a0c118654af03bcc9fdc9f1a332b4ad7ec55.
Pull in jonathanj's updated work.
Merge pull request #13 from twisted-infra/upgrade-trac-1.0.1

Upgrade trac 1.0.1