Public docker image live, updated docs

********* PEOPLE *************
Primary reviewer: @suntzu86 

Reviewers:

********* DESCRIPTION **************
Branch Name: sclark_332_set_up_public_docker
Ticket(s)/Issue(s): Closes #332 

********* TESTING DONE *************

Tested on dev and personal linux box
Why not link this section back to quick install? We have 3 entirely duplicate versions of this instruction set.