inconsistent unescaping in relpath basename and appendpath

[Aaron Bentley]

The basename and relpath config vars and appendpath config policy perform unescaping on file:// urls, but not other urls.

Given the following locations.conf:
[file:///bazaar.launchpad.net/~launchpad-pqm/launchpad/stablefun]
push_location = a{basename}q
submit_branch = a
submit_branch:policy = appendpath
public_location = a{relpath}q

[bzr+ssh://bazaar.launchpad.net/~launchpad-pqm/launchpad/stablefun]
push_location = a{basename}q
submit_branch = a
submit_branch:policy = appendpath
public_location = a{relpath}q

$ bzr config push_location -d file:///bazaar.launchpad.net/~launchpad-pqm/launchpad/stablefun/%3c
a<q

$ bzr config push_location -d bzr+ssh://bazaar.launchpad.net/~launchpad-pqm/launchpad/stablefun/%3c
a%3Cq

$ bzr config submit_branch -d bzr+ssh://bazaar.launchpad.net/~launchpad-pqm/launchpad/stablefun/%3c
a/%3C

$ bzr config submit_branch -d file:///bazaar.launchpad.net/~launchpad-pqm/launchpad/stablefun/%3c
a/<

$ bzr config public_location -d file:///bazaar.launchpad.net/~launchpad-pqm/launchpad/stablefun/%3c
a<q

$ bzr config public_location -d bzr+ssh://bazaar.launchpad.net/~launchpad-pqm/launchpad/stablefun/%3c
a%3Cq

Probably the most common use of these facilities is to compose URLs, so the escaped value would be more useful.