v0.0.9 - proof of assets ("audit") mode added

This release adds two new methods auditprove and auditverify. In short it allows proof of holding an amount of bitcoin in a range between minimum and maximum values, across N utxos where none of the utxos are revealed. See the auditor-docs folder for more details and instructions on how to use.

Some additional testing has also been added, but the pre-existing anonymous usage tokens functionality is unchanged.

(Note that 0.0.8 was removed as it omitted a necessary component - the proof message from the user label).