windows: use normalized path to check repository nesting...
windows: use normalized path to check repository nesting
current "localrepository._checknested()" uses specified path itself to
compare against subrepo pathes.
it is invoked from "hgsubrepo.subrepo()" or pathauditor (as callback),
and both use "os.sep" as separator.
this causes unexpected nesting check result, if subrepo configuration
uses "/" as path separator for sub repo path.
this path uses "/" to join path components (or apply "util.pconvert()"
on path) to normalize.
