Address review comment: Explain where certificates come from.
Address review comment: Explain where certificates come from.

1d4Nf6/flocker,1d4Nf6/flocker,jml/flocker,jml/flocker,w4ngyi/flocker,hackday-profilers/flocker,AndyHuu/flocker,adamtheturtle/flocker,wallnerryan/flocker-profiles,agonzalezro/flocker,hackday-profilers/flocker,mbrukman/flocker,agonzalezro/flocker,LaynePeng/flocker,runcom/flocker,lukemarsden/flocker,moypray/flocker,AndyHuu/flocker,LaynePeng/flocker,1d4Nf6/flocker,mbrukman/flocker,jml/flocker,achanda/flocker,Azulinho/flocker,adamtheturtle/flocker,w4ngyi/flocker,AndyHuu/flocker,lukemarsden/flocker,lukemarsden/flocker,moypray/flocker,runcom/flocker,Azulinho/flocker,mbrukman/flocker,wallnerryan/flocker-profiles,LaynePeng/flocker,hackday-profilers/flocker,achanda/flocker,wallnerryan/flocker-profiles,adamtheturtle/flocker,agonzalezro/flocker,achanda/flocker,w4ngyi/flocker,moypray/flocker,Azulinho/flocker,runcom/flocker