New API

As a preparation for 0.2 series, I have update API,
to be more compatible with official Java Servlet API. It is also lot closer to CXXSP api - another project aiming at providing servlet-like API to C++ writer, although taking slighlty different approach to the problem.

I am working on getting CXXSP's C++ Server Pages support ported over to work with CPPSERV. Now that APIs are so close, it should be easy to do