Re: p:hash : add reference and replace sha1 by sha with a version parameter

I'm ok with the proposed changes.

/ "Innovimax SARL" <innovimax@gmail.com> was heard to say:
| The value of the algorithm option must be a QName. If it does not have a
| prefix, then it must be one of the following values: "crc", "md", "sha",
| "whirlpool" and "ripemd".

I've never heard of whirlpool. I've heard of ripemd, but have no idea
how to implement it. Are those five exhaustive, or are there other
popular algorithms?

| The value of the version option must be a string.

You made version required, but I wonder if we should give it an
algorithm-specific default? version=1 if algorithm=sha, 5 if md. That
way, for crc and other algorithms that don't have a version, it won't
be an error to leave it out.

                                        Be seeing you,
                                          norm

-- 
Norman Walsh <ndw@nwalsh.com> | Virtuous people often revenge
http://nwalsh.com/            | themselves for the constraints to which
                              | they submit by the boredom which they
                              | inspire.--Gustave Le Bon