httpmessage: a library for http messaging

The httpmessage package is not a HTTP server library or a HTTP client library. It tries instead to be a HTTP peer library, allowing programs to more easily speak HTTP to one another. The design of httpmessage had writing a proxy server in mind, so it tries to preserve the integrity of HTTP messages so they can be modified and retransmitted if desired. Hopefully, the library is well suited to writing both clients and servers, but it does not assume that the program using it is a client or a server.