[MERGE][RFC] Add simple revision serializer based on RIO.

[Andrew Bennetts]

Alexander Belchenko wrote:
[...]
> In the past I wrote Pyrex extension for bencode. But it was rejected by  
> Aaron, because its benefits was not clearly visible at that time.

Cool, I might dig that up and take a look.

Although, personally, I'd skip Pyrex entirely and go straight to pure C.
bencode isn't very complex, and Pyrex really only gets you halfway to the
speed benefits of C.  Pyrex's real strength is as a easy way to write
bindings for C libraries, it's a bit mixed as a tool for writing faster
Python modules.

-Andrew.