Add Bandits to moe examples

********* PEOPLE *************
Primary reviewer: @sc932 

Reviewers: @suntzu86 

********* DESCRIPTION **************
Branch Name: norases_386_add_bandits_to_moe_examples
Ticket(s)/Issue(s): #386   

********* TESTING DONE *************
make test
make style-test
I'd scatter a few more comments in here. We want this to be over verbose with comments. This may be the first time someone has seen MOE and we want to be super explicit (to the point of being over explicit) about each part here. This is the demo/tutorial for someone who has seen nothing else. (Talk about in a few words that we have many bandits, what subtypes are, what an allocation is, etc, you can also link to other docs.)