Added broadcasting packets with options. And GlobalState Extension trait to easily `state.broadcast(&packet, opts).await;`

[Sweattypalms]

Better broadcasting. You can simply do state.broadcast(&packet, options); and it broadcasts to either: All entities, or specifically the entities mentioned with the BroadcastOptions::default().only(entities);. Can also have both Sync and Async callbacks using

BroadcastOptions::default().with_async_callback(|entity, state| async move {
// do whatever
});

Or for Sync callbaks

BroadcastOptions::default().with_sync_callback(move |entity, state| {
// do whatever
});