xenapi: Request a username if there is non in the URI
xenapi: Request a username if there is non in the URI

Use virRequestUsername and virRequestPassword.

soulxu/libvirt-xuhj,andreabolognani/libvirt,wiedi/libvirt,emaste/libvirt,amery/libvirt-vserver,eskultety/libvirt,rbu/libvirt,zhlcindy/libvirt-1.1.4-maintain,danwent/libvirt-ovs,warewolf/libvirt,datto/libvirt,fabianfreyer/libvirt,libvirt/libvirt,amery/libvirt-vserver,rmarwaha/libvirt,wiedi/libvirt,libvirt/libvirt,shugaoye/libvirt,novel/fbsd-libvirt,emaste/libvirt,elmarco/libvirt,jeckersb/libvirt,novel/fbsd-libvirt,fabianfreyer/libvirt,jeckersb/libvirt,iam-TJ/libvirt,rbu/libvirt,shugaoye/libvirt,rlaager/libvirt,olafhering/libvirt,shugaoye/libvirt,bjzhang/libvirt,agx/libvirt,amery/libvirt-vserver,jfehlig/libvirt,siboulet/libvirt-openvz,foomango/libvirt,wiedi/libvirt,bjzhang/libvirt,trainstack/libvirt,novel/fbsd-libvirt,rmarwaha/libvirt1,taget/libvirt,zippy2/libvirt,rbu/libvirt,jeckersb/libvirt,bjzhang/libvirt,siboulet/libvirt-openvz,foomango/libvirt,fabianfreyer/libvirt,VenkatDatta/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,sshah-solarflare/Libvirt-PCI-passthrough-,usc-isi/libvirt,olafhering/libvirt,trainstack/libvirt,datto/libvirt,rmarwaha/libvirt1,sshah-solarflare/Libvirt-PCI-passthrough-,wiedi/libvirt,jeckersb/libvirt,nertpinx/libvirt,rmarwaha/libvirt1,emaste/libvirt,elmarco/libvirt,leilihh/libvirt,iam-TJ/libvirt,shugaoye/libvirt,warewolf/libvirt,jardasgit/libvirt,dumbbell/libvirt,jardasgit/libvirt,agx/libvirt,leilihh/libvirt,rmarwaha/libvirt1,warewolf/libvirt,soulxu/libvirt-xuhj,crobinso/libvirt,rmarwaha/libvirt,warewolf/libvirt,elmarco/libvirt,warewolf/libvirt,warewolf/libvirt,siboulet/libvirt-openvz,usc-isi/libvirt,fabianfreyer/libvirt,dumbbell/libvirt,rmarwaha/libvirt,jfehlig/libvirt,novel/fbsd-libvirt,olafhering/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,foomango/libvirt,iam-TJ/libvirt,foomango/libvirt,eskultety/libvirt,crobinso/libvirt,iam-TJ/libvirt,jfehlig/libvirt,dumbbell/libvirt,zippy2/libvirt,trainstack/libvirt,fabianfreyer/libvirt,libvirt/libvirt,kantai/libvirt-vfork,emaste/libvirt,danwent/libvirt-ovs,bjzhang/libvirt,novel/fbsd-libvirt,andreabolognani/libvirt,cbosdo/libvirt,taget/libvirt,eskultety/libvirt,zhlcindy/libvirt-1.1.4-maintain,rbu/libvirt,eskultety/libvirt,datto/libvirt,kantai/libvirt-vfork,soulxu/libvirt-xuhj,andreabolognani/libvirt,dumbbell/libvirt,jardasgit/libvirt,wiedi/libvirt,zippy2/libvirt,agx/libvirt,soulxu/libvirt-xuhj,olafhering/libvirt,jeckersb/libvirt,iam-TJ/libvirt,amery/libvirt-vserver,novel/fbsd-libvirt,VenkatDatta/libvirt,taget/libvirt,novel/fbsd-libvirt,rmarwaha/libvirt1,zhlcindy/libvirt-1.1.4-maintain,agx/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,siboulet/libvirt-openvz,zippy2/libvirt,kantai/libvirt-vfork,jeckersb/libvirt,crobinso/libvirt,trainstack/libvirt,libvirt/libvirt,rlaager/libvirt,trainstack/libvirt,bjzhang/libvirt,agx/libvirt,usc-isi/libvirt,zhlcindy/libvirt-1.1.4-maintain,datto/libvirt,siboulet/libvirt-openvz,warewolf/libvirt,rmarwaha/libvirt,taget/libvirt,rmarwaha/libvirt,novel/fbsd-libvirt,trainstack/libvirt,leilihh/libvirt,nertpinx/libvirt,foomango/libvirt,usc-isi/libvirt,amery/libvirt-vserver,andreabolognani/libvirt,dumbbell/libvirt,danwent/libvirt-ovs,jardasgit/libvirt,elmarco/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,leilihh/libvirt,danwent/libvirt-ovs,emaste/libvirt,novel/fbsd-libvirt,rlaager/libvirt,zhlcindy/libvirt-1.1.4-maintain,nertpinx/libvirt,danwent/libvirt-ovs,soulxu/libvirt-xuhj,taget/libvirt,iam-TJ/libvirt,jeckersb/libvirt,rmarwaha/libvirt1,cbosdo/libvirt,eskultety/libvirt,jardasgit/libvirt,kantai/libvirt-vfork,kantai/libvirt-vfork,rmarwaha/libvirt,emaste/libvirt,rlaager/libvirt,rlaager/libvirt,wiedi/libvirt,usc-isi/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,dumbbell/libvirt,andreabolognani/libvirt,cbosdo/libvirt,elmarco/libvirt,leilihh/libvirt,datto/libvirt,iam-TJ/libvirt,emaste/libvirt,wiedi/libvirt,VenkatDatta/libvirt,cbosdo/libvirt,rbu/libvirt,shugaoye/libvirt,trainstack/libvirt,leilihh/libvirt,jfehlig/libvirt,crobinso/libvirt,cbosdo/libvirt