Crafty server library (0.5.3) uses wrong type check for Crafty.timer.stop()

[skysyk]

For the Crafty server library, the type check for tick on line 889 should be for "object" instead of "number" since setInterval returns an object in Node.js.

[mk-pmb]

The Node.js API docs on timers, section unref describe "The opaque value returned by setTimeout and setInterval", so I guess crafty should have the least expectations possible, because I understand "opaque" as "don't rely on (or even care about) specifics of the implementation". I usually only check truthiness on timer IDs.