Include ref log detail in commit, reset, etc.

When updating a ref at the direction of the user include a reason why
head was changed as part of the ref log (assuming it was enabled).

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-am.sh

@@ -447,7 +447,7 @@ do
 	parent=$(git-rev-parse --verify HEAD) &&
 	commit=$(git-commit-tree $tree -p $parent <"$dotest/final-commit") &&
 	echo Committed: $commit &&
-	git-update-ref HEAD $commit $parent ||
+	git-update-ref -m "am: $SUBJECT" HEAD $commit $parent ||
 	stop_here $this
 
 	if test -x "$GIT_DIR"/hooks/post-applypatch

git-applypatch.sh

@@ -204,7 +204,7 @@ echo Wrote tree $tree
 parent=$(git-rev-parse --verify HEAD) &&
 commit=$(git-commit-tree $tree -p $parent <"$final") || exit 1
 echo Committed: $commit
-git-update-ref HEAD $commit $parent || exit
+git-update-ref -m "applypatch: $SUBJECT" HEAD $commit $parent || exit
 
 if test -x "$GIT_DIR"/hooks/post-applypatch
 then

git-branch.sh

@@ -117,4 +117,4 @@ then
 		die "cannot force-update the current branch."
 	fi
 fi
-git update-ref "refs/heads/$branchname" $rev
+git update-ref -m "branch: Created from $head" "refs/heads/$branchname" $rev

git-commit.sh

@@ -676,7 +676,8 @@ then
 		rm -f "$TMP_INDEX"
 	fi &&
 	commit=$(cat "$GIT_DIR"/COMMIT_MSG | git-commit-tree $tree $PARENTS) &&
-	git-update-ref HEAD $commit $current &&
+	rlogm=$(sed -e 1q "$GIT_DIR"/COMMIT_MSG) &&
+	git-update-ref -m "commit: $rlogm" HEAD $commit $current &&
 	rm -f -- "$GIT_DIR/MERGE_HEAD" &&
 	if test -f "$NEXT_INDEX"
 	then

git-reset.sh

@@ -48,7 +48,7 @@ then
 else
 	rm -f "$GIT_DIR/ORIG_HEAD"
 fi
-git-update-ref HEAD "$rev"
+git-update-ref -m "reset $reset_type $@" HEAD "$rev"
 
 case "$reset_type" in
 --hard )