Make it possible to intercept and expand upon the unknown origin error.

We add another configuration option that enables stack traces of 
warnings.
Add a more beatiful builder pattern to PacketAdapter.

We can't use a traditional builder pattern though, as it's commonly 
used for constructing inner anonymous classes. But we can do the next 
best thing and create a builder for the parameters themselves.

Here's what the new syntax looks like:
  new PacketAdapter(params(this, 1, 2, 3).clientSide()) {
      @Override
      public void onPacketReceiving(PacketEvent event) {
          // Your code here
      }
  };
  
Where "this" referes to your plugin.