net.http.server: remove undone hijack_response().
mod_favicon: refactor code, and hook directly to server handler.
mod_http: depend on mod_favicon.
mod_http: rectify previous commit, and load mod_favicon using the add_host method.
mod_announce: cleanup code.
mod_announce: finish and fix previous commit.
mod_announce: correct typo.
mod_announce: do not attempt routing bodyless messages.