request help: use this lib in nginx stream subsystem

[tzssangglass]

Hi folks, thank you for open sourcing this lib.

I tried using this lib in the Nginx stream subsystem, and it works well, but I found that the judgment here always comes up when running the test case:

lua-resty-logger-socket/lib/resty/logger/socket.lua

Lines 31 to 39 in 15cc1c2

	if not ngx.config or not ngx.config.ngx_lua_version
	or ngx.config.ngx_lua_version < 9003 then
	is_exiting = function() return false end
	ngx_log(CRIT, "We strongly recommend you to update your ngx_lua module to "
	.. "0.9.3 or above. lua-resty-logger-socket will lose some log "
	.. "messages when Nginx reloads if it works with ngx_lua module "
	.. "below 0.9.3")

In the Nginx http subsystem, ngx.config looks like this:

{
  debug = true,
  nginx_configure = <function 1>,
  nginx_version = 1019009,
  ngx_lua_version = 10020,
  prefix = <function 2>,
  subsystem = "http"
}

and in Nginx stream subsystem,ngx.config looks like this:

{
  debug = true,
  nginx_configure = <function 1>,
  nginx_version = 1019009,
  ngx_lua_version = 10,
  prefix = <function 2>,
  subsystem = "stream"
}

I would be happy to submit a PR to improve this issue if you agree to be compatible with Nginx streams subsystem here.