added link on how to setup wss on android to the readme (#141)
removed possible InterruptedException(#122), made sure that all created threads will be stopped when binding server socket fails, and minor changes
made SSLSocketChannel2 also work on SocketChannels in blocking mode and therefore"generalized" WebSocketServerFactory and WebSocketClientFactory
fixed case in which onClose's would be CloseFrame.ABNORMAL_CLOSE wrongly and made WebSocketImpl work without SelectionKeys
simplified WebSocketClient by using blocking instead of nonblocking channels