#1 Interceptors for assignment1

[ihnames]

Andras' solution of assignment1 currently lacks interceptor-functionality. Since interceptors might help us solve assignment 2, we should add a means of inserting interceptors as soon as possible.

The easiest way to accomplish this may be to implement some method that creates genaral purpose javax.servlet.Filter instances and adds them to the server's filter-chain. But if somebody else has a better solution, feel free to implement it that way.