pivpn: add source code link, license/language tags

README.md

@@ -727,7 +727,7 @@ _See also: [IT Asset Management]([Ralph](#it-asset-management))_
 - [Nebula](https://github.com/slackhq/nebula) - A scalable p2p VPN with a focus on performance, simplicity and security.
 - [ocserv](http://www.infradead.org/ocserv/) - Cisco AnyConnect-compatible VPN server
 - [OpenVPN](https://community.openvpn.net) - Uses a custom security protocol that utilizes SSL/TLS for key exchange.
-- [PiVPN](https://www.pivpn.io/) - The simplest way to setup and manage a VPN, designed for Raspberry Pi. 
+- [PiVPN](https://www.pivpn.io/) - The simplest way to setup and manage a VPN, designed for Raspberry Pi. ([Source Code](https://github.com/pivpn/pivpn)) `MIT` `Shell`
 - [Pritunl](http://pritunl.com/) - OpenVPN based solution. Easy to set up.
 - [SoftEther](https://www.softether.org/) - Multi-protocol software VPN with advanced features
 - [sshuttle](https://github.com/sshuttle/sshuttle) - Poor man's VPN.