xtaci/kcptun v20190714

support `-tcp` option for linux

on GitHub

1. support -tcp option for linux(EXPERIMENTAL) . To enable tcp transmission, you should enable it on both client and server, supported only under LINUX with iptables, require root privilege.

discussion on this release:
#696

$ go version
go version go1.12.7 linux/amd64

$ uname -a
Linux DESKTOP-7FL7RC4 4.4.0-18362-Microsoft #1-Microsoft Mon Mar 18 12:02:00 PST 2019 x86_64 x86_64 x86_64 GNU/Linux

$ shasum *.tar.gz
89beb1c88422d6a73b6693f07290063f2fddf76d  kcptun-linux-amd64-20190714.tar.gz
ea7219013ee7df42b431add0908f3c453d0d2108  kcptun-darwin-amd64-20190714.tar.gz
49ae80d62d2d68001a04dac3272de08985d7001c  kcptun-windows-amd64-20190714.tar.gz
18a7310ad1da92fc5b35ab9d03a8c5985618fe41  kcptun-freebsd-amd64-20190714.tar.gz
b01221824e794bcd3f26246ea0c3af36649a2651  kcptun-linux-386-20190714.tar.gz
8faf525b847cda5c0f1022f1b496a2ecec770bd5  kcptun-windows-386-20190714.tar.gz
ba7f56218aa7ee3624aa839bf73a6217b87111a8  kcptun-linux-arm5-20190714.tar.gz
71f8830ee8a5b81006c3727e8d8237acd4ff2c5e  kcptun-linux-arm6-20190714.tar.gz
c5c63a1e6f713c40368c41e670b59415ad725079  kcptun-linux-arm7-20190714.tar.gz
2fea43afbfe6eb133d8633042d33aca42e3a042a  kcptun-linux-arm64-20190714.tar.gz
bdf95340c0bda0b940c0e35ed1d97f56062c6413  kcptun-linux-mipsle-20190714.tar.gz
2abf7c0fda32da7df277c9f0a80a71f5d38fca05  kcptun-linux-mips-20190714.tar.gz

$ date
Sun Jul 14 18:31:42 CST 2019