Added Bandit UCB1-tuned implementation

********* PEOPLE *************
Primary reviewer: @sc932 

Reviewers: @suntzu86 

********* DESCRIPTION **************
Branch Name: norases_366_ucb1_tuned_bandit
Ticket(s)/Issue(s): #366  

********* TESTING DONE *************
make test
make style-test
Also in the docstring for this class, I'd explicitly describe how it is supposed to be used and point to one of the existing UCBs as an example. That is, the user is needs to fill in the UCB confidence bound and everything else is already handled.