Fixes and cleanups to hgeditor: - "HG: merge resolve" isn't supported for a long time now. - detection of unchanged commit message if signing is turned off. - don't add manifest hash to commit message if not signing.

#!/bin/sh

hg init
echo 123 > a
hg add a
hg commit -m "first" -d "0 0" a
mkdir sub
echo 321 > sub/b
hg add sub/b
hg commit -m "second" -d "0 0" sub/b
cat sub/b
hg co 0
cat sub/b
ls sub

true