rewrite client demo by lua, remove old C version client demo

examples/client.lua

@@ -0,0 +1,35 @@
+package.cpath = "luaclib/?.so"
+
+local socket = require "clientsocket"
+local cjson = require "cjson"
+
+local fd = socket.connect("127.0.0.1", 8888)
+
+local last
+local result = {}
+
+local function dispatch()
+	while true do
+		local status
+		status, last = socket.recv(fd, last, result)
+		if status == nil then
+			error "Server closed"
+		end
+		if not status then
+			break
+		end
+		for _, v in ipairs(result) do
+			print(v)
+		end
+	end
+end
+
+while true do
+	dispatch()
+	local cmd = socket.readline()
+	if cmd then
+		socket.send(fd, cmd)
+	else
+		socket.usleep(100)
+	end
+end