Implementing HTTP...

* [RFC2616_CODINGS,NEW] New module implementing content and transfer coding values. Chunked transfer coding is not yet implemented (TODO).
* [RFC2616_DATE,EXT,SC,DOC] Vastly improved the support for HTTP date-time representations.
* [RFC2616_DCG,SC] Simplified code due to replcing modules.
* [RFC2616_GENERIC,DOC] Added documentation for chatset//2.