conf: snapshot: Extract code to generate default external file names
conf: snapshot: Extract code to generate default external file names

zippy2/libvirt,andreabolognani/libvirt,crobinso/libvirt,nertpinx/libvirt,libvirt/libvirt,taget/libvirt,jardasgit/libvirt,rlaager/libvirt,fabianfreyer/libvirt,datto/libvirt,andreabolognani/libvirt,andreabolognani/libvirt,datto/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,jfehlig/libvirt,eskultety/libvirt,zippy2/libvirt,olafhering/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,olafhering/libvirt,datto/libvirt,datto/libvirt,andreabolognani/libvirt,libvirt/libvirt,jardasgit/libvirt,rlaager/libvirt,eskultety/libvirt,crobinso/libvirt,olafhering/libvirt,andreabolognani/libvirt,zippy2/libvirt,nertpinx/libvirt,eskultety/libvirt,VenkatDatta/libvirt,libvirt/libvirt,rlaager/libvirt,VenkatDatta/libvirt,taget/libvirt,fabianfreyer/libvirt,zippy2/libvirt,taget/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,rlaager/libvirt,jfehlig/libvirt,taget/libvirt,jardasgit/libvirt,VenkatDatta/libvirt,nertpinx/libvirt,nertpinx/libvirt,eskultety/libvirt,jfehlig/libvirt,crobinso/libvirt,olafhering/libvirt,rlaager/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,datto/libvirt,eskultety/libvirt,crobinso/libvirt,libvirt/libvirt,fabianfreyer/libvirt,taget/libvirt