update link on authentication.rst
update link on authentication.rst

agonzalezro/flocker,adamtheturtle/flocker,agonzalezro/flocker,AndyHuu/flocker,AndyHuu/flocker,agonzalezro/flocker,w4ngyi/flocker,achanda/flocker,AndyHuu/flocker,achanda/flocker,wallnerryan/flocker-profiles,wallnerryan/flocker-profiles,moypray/flocker,adamtheturtle/flocker,hackday-profilers/flocker,adamtheturtle/flocker,moypray/flocker,mbrukman/flocker,1d4Nf6/flocker,w4ngyi/flocker,hackday-profilers/flocker,achanda/flocker,mbrukman/flocker,wallnerryan/flocker-profiles,w4ngyi/flocker,moypray/flocker,mbrukman/flocker,hackday-profilers/flocker,1d4Nf6/flocker,1d4Nf6/flocker