Merge branch 'sp/reflog' into next

* sp/reflog:
  Enable ref log creation in git checkout -b.
  Create/delete branch ref logs.
  Include ref log detail in commit, reset, etc.
  Change order of -m option to update-ref.
  Correct force_write bug in refs.c
  Change 'master@noon' syntax to 'master@{noon}'.
  Log ref updates made by fetch.
  Force writing ref if it doesn't exist.
  Added logs/ directory to repository layout.
  General ref log reading improvements.
  Fix ref log parsing so it works properly.
  Support 'master@2 hours ago' syntax
  Log ref updates to logs/refs/<ref>
  Convert update-ref to use ref_lock API.
  Improve abstraction of ref lock/write.

git-commit.sh

@@ -687,7 +687,8 @@ 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