Press F5 can refresh Submodule Diff Dialog

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Reorder string table

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>
Add submodule update button in Submodule Diff Dialog

Signed-off-by: Sup Yut Sum <ch3cooli@gmail.com>