openvpn: Fix verify script.

Former versions of openvpn called the script where the arguments
in the certificate's common name where separated by /.
Now, those are separated by ", " (comma, space).
pakfire: Prevent an infinite loop with empty server list.
Create core update 75.
openvpn: Move verify script out of configuration directory.
Move Core Updates 70-74 to oldcore directory.
close core75.