Add a closing cross in Notify independant from actions

[AxelMolina1]

When using Notify, we can add a button to close the notification.
In a multiline notification, the actions are forced on the bottom of the notification.

The problem is that I would want active actions (i.e. actions doing something) on the bottom and also a cross on top right to simply close the notification without doing an action.

Proposal : Add the option to have a closing cross independant from actions so we can have active actions on bottom and a simple closing cross on top right