move platform.mk out from makefile
netpack for gate
rewrite watchdog/agent, use new gate
rewrite client demo by lua, remove old C version client demo
c/s json protocol example
Merge pull request #84 from cloudwu/netpack

lua version gate and new example
remove old client
Merge branch 'netpack'
Merge pull request #1 from cloudwu/master

合并netpack