Event log parsing requires knowning both the public key and signing
parameters. Symmantically, this information should be from an attested
public key blob, not additional data passed by the client.
Introduce a new method for parsing an AIK's public key blob, returning
a new AIKPublic struct.
We plan to identify AIKs based on their public key. The raw blob should
be available via the AttestationParameters, but we hope that users will
only use that struct for generating challenges.
Because this parses the public key on AIK creation and loading, this PR
should have existing coverage.
* Refactor serialized keys into own structure, in preparation for making Key an interface.
* Refactor key logic into separate structures for each platform/TPMversion invariant.
* Implement review feedback
