module to check if there is Internet access

 LWP::Online will try to verify, as accurately as it can, if the
 host has any Internet access: it will check if there is basic
 network access, DNS connectivity and it will also check whether
 one from a whole set of transport (HTTP, HTTPS, FTP, and so on) is
 actually available.
 .
 The exported 'online' function can also be used by other modules to
 skip the tests which require Internet connectivity.