tests/test-issue433

hg: say 'hg update' instead of 'hg up' in merge status message

Includes the change to the message itself, along with several test
output files that also had to change.

#!/bin/sh
# http://mercurial.selenic.com/bts/issue433

hg init a
cd a
echo a > a
hg commit -Ama

hg parents -r 0 doesnotexist
true