Created a HMAC authorization provider for Wookie REST APIs (see WOOKIE-279, and linked discussion with Tien). This will be used in place of "plaintext" API keys in Wookie 2.x

git-svn-id: https://svn.apache.org/repos/asf/wookie/trunk@1569518 13f79535-47bb-0310-9956-ffa450edef68