add restore action

[komlenic]

An action to restore a backup of a site/project on a node should be added. When called without any arguments such as drubs restore prod a prompt should present a numbered list of available backups from which to choose to restore, and automatically request verification to install the most recent backup.

If Y is entered, the most recent backup will be restored (and this can be automated using the '-y' flag like: drubs restore prod -y.

If an integer is entered (corresponding to the numbered list of available backups that is presented) then that specific backup should be restored.

Otherwise, if N is entered (or any other input), exit without doing anything.