Add Cglib support for client proxying

[刘正阳 | bytejava.cn]

Now we have a default JDK proxy implementation, JDK Proxy use class code generating and can proxy interfaces. Although we have assumed that the proxyed class is interface, we can add an alternative of proxy implementation with cglib, javaassist, asm etc.

[刘正阳 | bytejava.cn]

Finished with #25