修改.giignore文件

忽略下列文件
/CoreJava/ImageViewer/doc/
/CoreJava/ImageViewer/bin/
/JavaNetworkProgramming/ch4-NonBlockingCommunication/bin/
/JavaNetworkProgramming/ch4-NonBlockingCommunication/doc/
javaNetworkProgramming chapter 4 example BlockingCommunication

java网络编程精解第四章非阻塞通信中的阻塞服务器!