Clarified message when nothing to merge is seen. Sometimes there's a non-tip head waiting to be merged, especially after pulling in remote changes while there were local modifications in the working directory which had to be committed before 'hg merge' can work.

#!/bin/sh

mkdir t
cd t
hg init
echo a > a
hg add a
hg commit -m "test" -d "1000000 0"
hg verify
hg parents
hg status
hg rollback
hg verify
hg parents
hg status