Cryptacular and KeySupport/X509Support

[Rod Widdowson]

I took an AI a few weeks ago to look at potential overlap between the
Key/X509 support classes in OpenSAML and the same in Cryptacular.

As it turns out there are not too many overlaps.  The obvious ones are:

	KeySupport.matchKeyPair (OpenSAML) is mirrored by KeyPairUtil
isKeyPair (Cryptacular)

	KeySupport.decodePrivateKey by KeyPairUtil.decodePrivateKey  (with
some restrictions on what an empty password is)

	KeySupport.getKeyLength has analogues in KeyPairUtil.length(Class),
but the latter does not have support for SecretKey (and so is not usable).

	X509Support.determineEntityCertificate (OpenSAML) is mirrored by
CertUtil.findEntityCertificate (hah! Another 'entity' is another context
sensitive term).

	Finally there is X509Support.decodeCertificate whose multiple
implementations are pretty much straight calls to various methods in
CertUtil.

I'm not sure what (if anything) we want to do from here on in.  I've changed
the IdP Parsing code to use Cryptacular as appropriate in the cases above.
I see that there is some use of these methods scattered across OpenSAML.  I
could do the mechanical change from one to the other in OpenSAML if we think
that this is useful.

Rod