Need simply fix for openvpn-2.4

[pcgyver007]

For OpenVPN 2.3.x below config was fine
plugin /usr/lib/authy/authy-openvpn.so https://api.authy.com/protected/json <AUTH-KEY> nopam

For OpenVPN 2.4 plugin must has 2 arguments so must be:
plugin "/usr/lib/authy/authy-openvpn.so" "https://api.authy.com/protected/json <AUTH-KEY> nopam"
So three params for plugin must be in quotes. If not then in log:
Options error: Unrecognized option or missing or extra parameter(s) in /etc/openvpn/openvpn.conf:336: plugin (2.4.0)
and openvpn doesn't start.

Command to install authy in openvpn.conf must be fixed.