check_vpn: better device parsing for ssh plugin
check_vpn: tun/tap device for ssh controlled by command line
check_vpn: smarter device allocation
check_vpn: smarter device allocation, core functionality
check_vpn: improved openvpn runtime device detection
check_vpn: updated README.md for tun/tap devices
Merge pull request #8 from danfruehauf/tun_tap_ssh

check_vpn: tun/tap improvements for ssh plugin