Better error handling

[arthuro555]

I was working on a project that uses geckos.io, when I stumbled upon this error:

This error is really useless by itself, no additional console logs on the server nor any error handler triggered :/
Looking at the code, I am met with that error code being reused everywhere :/ The cause of the error is at all times swallowed, there is no way for me to know what the source of it is.

It would be nice if I could do something like server.onError(e => console.log(e)) or something similar to get more precise error messages...