RFS: ruby-varia-model

Hi team! Please upload new version of ruby-varia-model. It may break ruby-ridley and some other berkshelf related packages, but I'm preparing their updates. Thanks in advance.

RFS: berkshelf for bpo9

Hi team! Please upload berkshelf 4.3.5-2~bpo9+1 to backports. It was not fixed in time during the freeze so I was advised to provide it though backports. Branch stretch-backport in git repo. Thanks in advance.