Wireguard wiki page additional content

Hi,

Since the 0.0.20180724 Android client version addition of vpn
configurations via qr code is possible.

There is a package named qrencode that can be used to generate qr code from
a config file even in terminal using utf8 characters. I succesfully
imported a wireguard config from my headless Debian router via ssh directly
from a terminal with the following command:

cat profile.conf | qrencode -t UTF8 -o -


Maybe this can be added to the wiki since it can be very useful for
securely distributing vpn configs.

Regards,

Kertesz Laszlo