Make it possible to disable filtering for a pattern.
Rationale: Apparently there were no way to disable for example win32text extension locally.
RFC: Can it already be done another way?
#!/bin/sh
echo "[extensions]" >> $HGRCPATH
echo "mq=" >> $HGRCPATH
hg init a
cd a
echo a > a
hg ci -Ama
hg qnew a.patch
echo a >> a
hg qrefresh
hg qnew b.patch
echo b > b
hg add b
hg qrefresh
hg qnew c.patch
echo c > c
hg add c
hg qrefresh
hg qgoto a.patch
hg qgoto c.patch
hg qgoto b.patch