WireGuard root-less support for android

[Aurélien Chabot]

Hi,

I worked on a set of change to add root-less support of WireGuard for
android. The solution I choose is to use the wireguard-go library inside
the android application. Golang as a mechanism to export some native
binding quite easily to java. The set of patch need some feedback but
it's actually working well. I'd like to know if you think this is a good
direction to take for the android application.
The patch are in the thread but I used a submodule to integrate the
wireguard-go library inside the wireguard-android so at least this need
to be change with the official url if it's get merge. 

You can also find the set of change on my github :
https://github.com/trishika/wireguard-android
https://github.com/trishika/wireguard-go

Aurélien