Allow specifying build server.
Allow specifying build server.

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