added secret 'black box' file and class

need to add this to get master branch up to current. this commit has the new secret class im going to add in an external file. With this method Secret.new becomes a true "black box." The only issue i have right now is that you have to call one extra method area_51.secret to get the computed output. I will see if I can find a way to reduce that down to just one call on the class.