Re: nimx Error: no generic parameters allowed for ref

[yglukhov]

Or you can import nimx.system_logger in the main file. Updated 
[example](https://github.com/yglukhov/nimx/commit/d199b9be2f2e1f5c6974bc16ab03b010f3b96e99)
 and filed a [bug](https://github.com/nim-lang/Nim/issues/4433).