Bring the peer:filter event arguments into line with others

[DamonOehlman]

I was just using the peer:filter event in quickconnect and it was surprising to me (which means it will be more surprising to others) that the peer:filter event signature does not match other events signalller. While it is a little different in that the allow attribute needs to be passed back to the caller (and thus must be included in an object) not having the first argument as a peer id is a little confusing.

Perhaps the following signature would make more sense:

f(id, data) {}

Where data.allow is the current flag as to whether the peer will be recognised by the peer:announce handler or not.