Problem: The channel feature isn't working yet.
Solution: Add the connect(), disconnect(), sendexpr() and sendraw()
functions. Add initial documentation. Add a demo server.
Problem: MS-Windows channel code only supports one channel. Doesn't build
without netbeans support.
Solution: Get the channel index from the socket in the message. Closes#600.
Problem: The socket I/O is intertwined with the netbeans code.
Solution: Start refactoring the netbeans communication to split off the
socket I/O. Add the +channel feature.
