xtaci/kcptun v20190715

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 darwin/amd64

$ uname -a
Darwin xtacideMacBook-Pro.local 18.6.0 Darwin Kernel Version 18.6.0: Thu Apr 25 23:16:27 PDT 2019; root:xnu-4903.261.4~2/RELEASE_X86_64 x86_64

$ shasum *.tar.gz
cdcd760628b82420c231c132bec91fb4bae6ed1a  kcptun-linux-amd64-20190715.tar.gz
b664b8dbfca78b33beeaac20acda595ce4ecc76a  kcptun-darwin-amd64-20190715.tar.gz
1d2db7b5c27e8a93d53d8d319665ea5b5faa8e34  kcptun-windows-amd64-20190715.tar.gz
7a824478c80fe00d0372c8e35367d83d5ce1750c  kcptun-freebsd-amd64-20190715.tar.gz
d712bf429dd3bd41338a55f88db952e0ae64bfec  kcptun-linux-386-20190715.tar.gz
f99e5a26f519557c3758495a6823120502068b5b  kcptun-windows-386-20190715.tar.gz
dce06f556d62584f1b9344d2af4710cb35ba384f  kcptun-linux-arm5-20190715.tar.gz
d31f7e6531ac67d87fcc09916f6bed64c1b08bec  kcptun-linux-arm6-20190715.tar.gz
f8988e747d4f5237a928966796b6a839960ac3ad  kcptun-linux-arm7-20190715.tar.gz
054b157601fd83da4032334131a4a89fe2558052  kcptun-linux-arm64-20190715.tar.gz
94ed697dbe05fdc7302da4a4517bdd054057b0ab  kcptun-linux-mipsle-20190715.tar.gz
2e43796922390c7f4022611f791bdd9d3d45b207  kcptun-linux-mips-20190715.tar.gz

$ date
2019年 7月15日 星期一 14时00分05秒 CST```