git-revert: Revert revert message to old behaviour

git-revert: Revert revert message to old behaviour

When converting from the shell script, based on a misreading of the
sed invocation, the builtin included the abbreviated commit name,
and did _not_ include the quotes around the oneline message.

This fixes it.

[jc: with a fix for the typo/thinko spotted by Linus, and also
 removing the unwanted abbrev at the beginning.]

Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>