Add tests

[paulo-ferraz-oliveira]

@g-andrade: would it be too cumbersome to have potentially existing code test under Travis CI? Or is this request absurd and can be closed straight away?

[g-andrade]

If you're OK with labeling this issue as "utopic improvement" (assuming custom labels are allowed), I'd be OK with keeping it open :-).

Very unlikely to happen, but not technically impossible, although perhaps pointless if we start using SLikeNet instead, RakNet's maintained successor.