add: incomplete auto signature of authors;
add: levels of package combine.

Signed-off-by: liuyanghejerry <liuyanghejerry@126.com>
change: lock canvas at start if history exists.

Signed-off-by: liuyanghejerry <liuyanghejerry@126.com>
update: use compact mode if Qt version reaches 5.1.0.

Signed-off-by: liuyanghejerry <liuyanghejerry@126.com>