v0.2.0:
        * added key'd hash ability (using sha3-256/384 instead sha1/sha256) based on facebook key'd hmac salt/hash using
          SetKey() on the profile before any operation.
        * fixed the build.
        * added some tests for key'd hashes.
        * minor code rearrangement.
        * can be used concurrently lock-free.
        * bugfixes and code cleaning.
        * initial key'd hash tests & compatibility tests.