Fix virConnectOpen.*() name requirements
Fix virConnectOpen.*() name requirements

virConnectOpenAuth didn't require 'name' to be specified (VIR_DEBUG
used NULLSTR() for the output) and by default, if name == NULL, the
default connection uri is used.  This was not indicated in the
documentation and wasn't checked for in other API's VIR_DEBUG outputs.

jardasgit/libvirt,libvirt/libvirt,shugaoye/libvirt,nertpinx/libvirt,shugaoye/libvirt,zhlcindy/libvirt-1.1.4-maintain,zhlcindy/libvirt-1.1.4-maintain,andreabolognani/libvirt,zippy2/libvirt,jardasgit/libvirt,jardasgit/libvirt,agx/libvirt,crobinso/libvirt,datto/libvirt,eskultety/libvirt,agx/libvirt,jfehlig/libvirt,eskultety/libvirt,libvirt/libvirt,shugaoye/libvirt,zhlcindy/libvirt-1.1.4-maintain,elmarco/libvirt,olafhering/libvirt,shugaoye/libvirt,eskultety/libvirt,rlaager/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,eskultety/libvirt,VenkatDatta/libvirt,VenkatDatta/libvirt,olafhering/libvirt,agx/libvirt,cbosdo/libvirt,rlaager/libvirt,elmarco/libvirt,VenkatDatta/libvirt,crobinso/libvirt,jardasgit/libvirt,datto/libvirt,cbosdo/libvirt,VenkatDatta/libvirt,eskultety/libvirt,VenkatDatta/libvirt,fabianfreyer/libvirt,zippy2/libvirt,andreabolognani/libvirt,elmarco/libvirt,libvirt/libvirt,shugaoye/libvirt,taget/libvirt,cbosdo/libvirt,taget/libvirt,fabianfreyer/libvirt,olafhering/libvirt,jfehlig/libvirt,nertpinx/libvirt,datto/libvirt,rlaager/libvirt,agx/libvirt,crobinso/libvirt,datto/libvirt,andreabolognani/libvirt,taget/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt,elmarco/libvirt,elmarco/libvirt,nertpinx/libvirt,taget/libvirt,rlaager/libvirt,jfehlig/libvirt,agx/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,zippy2/libvirt,zippy2/libvirt,cbosdo/libvirt,nertpinx/libvirt,libvirt/libvirt,nertpinx/libvirt,andreabolognani/libvirt,crobinso/libvirt,taget/libvirt,cbosdo/libvirt,zhlcindy/libvirt-1.1.4-maintain,olafhering/libvirt,rlaager/libvirt,datto/libvirt,zhlcindy/libvirt-1.1.4-maintain