Add getCredentialSupport methods that taks the credential type as an argument.

In ELY-282 getCredentialSupport is being switched to check based on credential name, however at the mechanism level there is still a need to know that the correct type can also be obtained as a mechanism is also dependent on the type.

If we add getCredentialSupport(String credentialName, Class<?> credentialType) we can convert the methods that just take credential name to be default methods that call getCredentialSupport(credentialName, Object.class);