Implements OpenVPN 2.4 changes for Arch Linux (kind of)
Implements OpenVPN 2.4 changes for Arch Linux (kind of)

Since OpenVPN 2.4 is out on Arch, the script wasn't working completely because of this : https://www.archlinux.org/news/openvpn-240-update-requires-administrative-interaction/

There is a new path for OpenVPN server config. This is just needed on Arch for now, and you're probably not going to run an OpenVPN client on an OpenVPN server. 

Thus I modified the systemd script to use `/etc/openvpn/` and `server.conf` instead of the new `/etc/openvpn/server/` and `openvpn.conf`.

By using the same paths as the other distros, I avoid to rewrite the entire script to change the paths...

It's not 100% clean, but it works pretty well. If you have any objection please leave a comment.

Also, I updated the new service name.

As far as I tested, it's working fine on Arch Linux for now.

Fixes #63 and #61
Angristan/OpenVPN-install