Add an option allowing to update modules while updating Humhub core

[marc-farre]

In some other software, when you update the core, modules are also updated together.
I think it would help admins to have this option:

1. because some of them don't know that after updating Humhub the modules are not updated
2. it is safer, for major updates, to also update modules before AND after updating Humhub core, but few people know that