Move broadcasts out of cProtocol

[xoft]

I have a feeling you already have something like this at the cBroadcaster level - it does a DoWithChunk() and in the callback it calls the specific SendXYZ call on cClientHandle. So cWorld, cChunkMap and cChunk should already be broadcast-less when this change is fully implemented.

I'm not sure if any more refactoring is a good idea, it might make things too twisted to understand. I'd go with the current refactor only and then see if that is satisfactory.