Calculate ComputedId value outside of shibboleth idp

[Cantor, Scott]

> Turns out it was pretty trivial after all. The documentation says it's
> computed from the sha1 hash of the requestors entityid, the supplied
> attribute, and the salt, but it neglected to mentioned those three
> values were gratuitiously separated with a ! when calculating the hash
> 8-/.

Assume that you're joking, but of course the separator is quite necessary for reasons I guess I could point out, but will leave as an exercise for the reader.

-- Scott