KeyMint/SecureClock: Reverse dependency between keymint and secureclock.

This patch removes verifyAuthorization from the KeyMint spec in favor of
secureclock and the TimeStampToken. Timestamp has moved to secureclock
and the VerificationToken was removed from keymint. This reverses the
dependency between keymint and secureclock because keymint no imports
TimeStampToken and Timestamp from secureclock.

Test: Tested with CtsVerifier Fingerprint bound keys test.
Change-Id: I4e0bde0d77e74918e2b5483c30be8057417e3bf1