Necessary changes so that the licensing functionality can be
used in a JVM in FIPS 140 approved mode.
* Uses adequate salt length in encryption
* Changes key derivation to PBKDF2WithHmacSHA512 from a custom
approach with SHA512 and manual key stretching
* Removes redundant manual padding
Other relevant changes:
* Uses the SAH512 hash instead of the encrypted key bytes as the
key fingerprint to be included in the license specification
* Removes the explicit verification check of the encryption key
as this is implicitly checked in signature verification.