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.