[aerogear-dev] added rfc implementation

Hey guys, I've splitted the Google TOTP, Mobile-OTP and the real TOTP. I've added the rfc implementation and test using the test vectors. https://github.com/manzke/aerogear-otp-java/commit/2dd44978460aa3adfd7520... Before I start another pull request, it would be nice if you could review it and tell me if you are interested in. :) Bye, Daniel :)