Add console output as a return value to MetaLib#overflow

[twilit iron]

or, just return a string instead of creating a new type for no good reason
as well:

However, there's no way to programmatically find out why the method has failed ("No active guest active")
see image + output of metaxploit.scan_address(...) (though i don't remember if methods have been added to cover every requirement)

[static wharf]

I... I did not know that was available... I'm tired, i need to go to bed....