Bump version 2.2.0

Signed-off-by: Jianhui Zhao <[email protected]>

Bump version 2.1.0

Signed-off-by: Jianhui Zhao <[email protected]>

Bump version 2.0.0

Signed-off-by: Jianhui Zhao <[email protected]>

optimize code, remove depend luaposix in broker

Signed-off-by: zhaojh329 <[email protected]>