Access to underlying container buffers

We have a client Endpoint that happens to occasionally need to push a fair amount of data back to the peer via write(), and during performance testing we noted that the data was being chunked up into 16K buffers.

While searching for a way to tweak the buffer sizes similar to .NET/C# ClientWebSocketOptions.SetBuffer it looks like we do not have access from the Endpoint to the underlying container transport buffers. Ideally, something like exposing TCPNIOTransportBuilder.writeBuffersSize() params (perhaps via GrizzlyClientProperties?) for Grizzly to give us a way to hint at larger buffers.

If Grizzly is slowly being deprecated in favour of the NIO transport container, a way to change the send/recv buffers beyond the fixed 4K/17K sizes in 1.10 is requested.
#### Affected Versions
[1.10]