Fix handling of paths when run outside the repo.
The main problem was that dirstate.getcwd() returned just "",
which was interpreted as "we're at the repo root". It now returns
an absolute path.
The util.pathto function was also changed to deal with the "cwd is
an absolute path" case.
#!/bin/sh
echo "[extensions]" >> $HGRCPATH
echo "mq=" >> $HGRCPATH
echo % init
hg init a
cd a
echo % commit
echo 'base' > base
hg ci -Ambase -d '1 0'
echo % qnew mqbase
hg qnew -mmqbase mqbase
echo % qrefresh
echo 'patched' > base
hg qrefresh
echo % qdiff
hg qdiff | sed -e "s/\(+++ [a-zA-Z0-9_/.-]*\).*/\1/" \
-e "s/\(--- [a-zA-Z0-9_/.-]*\).*/\1/"
echo % qdiff dirname
hg qdiff . | sed -e "s/\(+++ [a-zA-Z0-9_/.-]*\).*/\1/" \
-e "s/\(--- [a-zA-Z0-9_/.-]*\).*/\1/"