Make hg paths and hg debugconfig work with -R/--repository option.
Commands that can use a repo, but don't need one, should be added
to the "optionalrepo" string, similar to the "norepo" string.
port:4:export
port:4:vaportight
port:4:import/export
FIXME: history is wrong here
port:1:1:-:eggs:import
port:1:2:+:eggs:vaportight
port:1:3:+:eggs:import/export
port:0:2:+:spam:export
port:0:1:+:spam:import
port:4:import/export