Implement HTTP level support

[bonifaido]

Problem Statement

It would be nice to analyze application level traffic and authenticate, make decisions based on that.

Proposed Solution

A nice and simple (compatible license, 2 plain C files) HTTP parser is https://github.com/h2o/picohttpparser

Alternatives Considered

Please briefly describe which alternatives, if any, have been considered, including merits of alternate approaches and tradeoffs being made.

Additional Context

Please provide any other information that may be relevant.

[baluchicken]

Partially done in: #158