Cocos2dx lua 3.10版本绑定cjson流程

如题，使用cocos2dx lua自带的json效率很低，接入cjson来处理：

1、找到frameworks\cocos2d-x\cocos\scripting\lua-bindings\manual\network\lua_extensions.c，修改：

#include "lua_extensions.h"

#if __cplusplus
extern "C" {
#endif
// socket
#include "luasocket/luasocket.h"
#include "luasocket/luasocket_scripts.h"
#include "luasocket/mime.h"
#include "lua/cjson/lua_cjson.h"

static luaL_Reg luax_exts[] = {
    {"socket.core",luaopen_socket_core},{"mime.core",luaopen_mime_core},{"cjson",luaopen_cjson },{NULL,NULL}
};

void luaopen_lua_extensions(lua_State *L)
{
    // load extensions
    luaL_Reg* lib = luax_exts;
    lua_getglobal(L,"package");
    lua_getfield(L,-1,"preload");
    for (; lib->func; lib++)
    {
        lua_pushcfunction(L,lib->func);
        lua_setfield(L,-2,lib->name);
    }
    lua_pop(L,2);

    luaopen_luasocket_scripts(L);
}

#if __cplusplus
} // extern "C"
#endif

2、android打包库里添加： frameworks\cocos2d-x\cocos\scripting\lua-bindings\proj.android\Android.mk

          ../../../../external/lua/cjson/strbuf.c \
          ../../../../external/lua/cjson/fpconv.c \
          ../../../../external/lua/cjson/lua_cjson.c \

3、ios平台暂时未处理，待续~~~