Handle JSONWebKey by value when making JWERecipient

[alee792]

See #360.

JSONWebKey as a key was not supported, but *JSONWebKey was. Simply added a new case to handle the value version. Tests still pass.

The second issue mentioned in #360 was a misread. The recipient, which contains the keyID, is added directly to the encrypter in the default case.

[CLAassistant]

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