pasta does not correctly handle bind errors with port ranges

[Paul Holzinger <pholzing@redhat.com>]

Hi all,
I found some issues with the pasta port binding logic, it does not 
correctly handle errors when trying to bind a port range.
Let's first bind a port so we can force an error condition it:
$ nc -l -p 8080 &
$ pasta -t 8080  true
Failed to bind any port for '-t 8080', exiting <-- fails as expected
$ pasta -t 8081 -t 8080  true
Failed to bind any port for '-t 8080', exiting <-- here it also fails 
correctly
$ pasta -t 8080-8081  true
<-- no error even though pasta could not bind 8080

Also besides this I find the error message less than ideal. It missing 
the errno from the bind syscall so important context gets lost (i.e. 
Address already in use vs Permission denied).