branch tc_url_rev: almost ready to merge

Hi tree-conflicts folks,

I think we're ready to merge tc_url_rev to trunk code-wise. But Julian,
could you maybe polish over the question/todo comments that were in your
initial patch (and survived), and remind us if we forgot something?

BTW, gstein and stsp were both +1 on merging to trunk earlier to"day" on IRC
(under the assumption that everything that's there is good). So am I.

Thanks,
~Neels