release of sha256/sha512 library

[David Mercer]

We are pleased to announce Version 0.21a, the initial functioning
release of Shaskell, our SHA2 library for (so far) ghc6.  It supports
sha256 and sha512 hashes in this version, and is "pure": no monads or
C libraries are involved!

Source and Ubuntu 5.04 binaries are at:
http://davidmercer.nfshost.com/projects/shaskell/
(Shaskell-0.21a.hs is the current release).

Project homepage is at:
http://davidmercer.nfshost.com/projects/shaskell/shaskell.html

Future releases will additionally support sha224, sha384, be
Cabal-ized, and supply wrappers for hashing files and other data
sources where the message length is not known in advance.

Special thanks to Dominic Steinitz for invaluable suggestions.

Any testing or feedback is of course welcome and appreciated!
It is released under the (BSD compatible) MIT X license.

Happy New Year, hopefully this will help improve the security of
future crypto systems written in Haskell.

Cheers,

-David Mercer
Tucson, AZ