bookmarks: update help text since moving into core
Clarifies the help text for the bookmarks command regarding the
requirements for pushing or pulling bookmarks.
Issue351: mq: qrefresh can create extra revlog entry
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init
$ hg qinit
$ echo b > b
$ hg ci -A -m foo
adding b
$ echo cc > b
$ hg qnew -f foo.diff
$ echo b > b
$ hg qrefresh
$ hg debugindex .hg/store/data/b.i
rev offset length base linkrev nodeid p1 p2
0 0 3 0 0 1e88685f5dde 000000000000 000000000000