convert/subversion.py: fix bad assumptions about SVN path naming
The SVN converter assumed that the trunk and branches paths were fixed,
and immediately under the base of the SVN URL. Fix the second assumption,
and allow the trunk and branches paths to be reconfigured.
Basic install:
$ make # see install targets
$ make install # do a system-wide install
$ hg debuginstall # sanity-check setup
$ hg # see help
See http://www.selenic.com/mercurial/ for detailed installation
instructions, platform-specific notes, and Mercurial user information.