Remove Array.prototype.diff prototype augmentation

[GeeWee]

In sync.js we're augmenting array with Array.prototype.diff
This can break other extensions looping over arrays (see e.g. gTile/gTile#22 (comment))

I think it would be best to remove the prototype augmentation, it's widely considered a bad idea in environments where code have to share a runtime.

[oae]

thank you for the feedback. I have removed it and will release it in the next version

[GeeWee]

Awesome! Thanks!