tests/test-serve.out

subrepo: handle svn tracked/unknown directory collisions

This happens more often than expected. Say you have an svn subrepository with
python code. Python would have generated unknown .pyc files. Now, you rebase
this setup on a revision where a directory containing python code does not
exist. Subversion is first asked to remove this directory when updating, but
will not because it contains untracked items. Then it will have to bring back
the directory after the merge but will fail because it now collides with an
untracked directory.

Using --force is not very elegant but it is much simpler than rewriting our own
purge command for subversion.

% Without -v
access log created - .hg/hgrc respected
% errors
% With -v
listening at http://localhost/ (bound to 127.0.0.1:HGPORT1)
% errors
% With -v and -p HGPORT2
listening at http://localhost/ (bound to 127.0.0.1:HGPORT2)
% errors
% With -v and -p daytime (should fail because low port)
abort: cannot start server at 'localhost:13': Permission denied
abort: child process failed to start
% errors
% With --prefix foo
listening at http://localhost/foo/ (bound to 127.0.0.1:HGPORT1)
% errors
% With --prefix /foo
listening at http://localhost/foo/ (bound to 127.0.0.1:HGPORT1)
% errors
% With --prefix foo/
listening at http://localhost/foo/ (bound to 127.0.0.1:HGPORT1)
% errors
% With --prefix /foo/
listening at http://localhost/foo/ (bound to 127.0.0.1:HGPORT1)
% errors