Shadowsocks SIP003 Integration

Warning: this experimental integration is nowhere near standard, and the functionality is added purely for fun, so do not expect any useful support. (#8)

The whole thing works like this:

Shadowsocks Client === Trojan Forward (Client-Side Plugin) ===== Trojan Server (Server-Side Plugin) === Shadowsocks Server

Pass a whole working trojan config to the --plugin-opts option of shadowsocks. Exclude remote_addr, remote_port, local_addr, and local_port for the client-side plugin, and local_addr and local_port for the server-side plugin, as they will be filled by shadowsocks. Note that you do need to fill in the target_addr and target_port fields of the client-side plugin to be the listening address and port of the shadowsocks server for it to work, but since shadowsocks refuses to cooperate, you'll have to set it every time you restart shadowsocks server.