Rename
Fix default number of IO threads

The default number of IO threads is either the half of available
processors or 2, which is greater.
Remove pseudo-multicast operation

It's not general operation and bad usability.
Fix pseudo-multicast structor

Unicast server side bulk write is defined by ContextTransportAggregate,
which is hold in EventLoopGroup. Any transport bulk write is defined
by DefaultTransportAggregate.
Add write(Object, SocketAddress)

write interface for non-connected UDP communication.
Change pipe line owner from EventLoop to Transport

The pipe line deal with transport-related events.
Fix TransportFuture interface
Add EncodeBuffer/DecodeBuffer/BufferSink

EncodeBuffer is a buffer class to encode messages, and DecodeBuffer
is to decode messages. BufferSink is interface to define how to be
written to Transport.
Fix to use DecodeBuffer as ByteBuffer wrapper

Instead of using ByteBuffer directly on receiving data at Channel,
use DecodedBuffer wrapping the ByteBuffer in a load pipe line.
Add output type parameter to Stage etc.

Stage and its related classes has two type parameters: I and O.
The I is input message type, used in the argument of process(),
and the O is output message type, used in the argument of proceed().
Add dedicated write buffer for Transport

To make use of direct byte buffer for write operation,
NioChildChannelTransport has its own write buffer.
Fix the proper name.
Add DecodeBuffer and EncodeBuffer implementations
Add methods to encode and decode
add read/write method for String

Add readString() to DecodeBuffer and writeString() to EncodeBuffer.
readString() needs CharsetDecoder and writeString() needs
CharsetEncoder.
Add support for signed variable byte codes

The implementations of signed variable byte codes exist in
skeletal class; AbstractDecodeBuffer and AbstractEncodeBuffer.
Fix readString() and writeString()

These methods contains a byte length handling.
Add method to EncodingBuffer and add tests
Remove segmented buffers

These classes is not used curretly.
Add byte array and ByteBuffer view for buffers