SECOAUTH-388: apply ClientCredentialsTokenEndpointFilter only if not already authenticated
Allow whitespace padding in private keys
Fix broken integration test

Recent changes to the sparklr sample mean that it is using a vanilla
basic auth entry point for the token endpoint.
SECOAUTH-366: add optional filter for token endpoint
SECOAUTH-366: don't clobber client_id by resetting authorizationParameters
Tidy imports
Add JWT support for RSA public key PEM formats.

This makes it possible to create an RsaVerifier with
a PEM encoded public key. Previously it could only be
done with a private key or an ssh-keygen format public
key.
Merge remote-tracking branch 'parent/master'