Merge pull request #3554 from tianon/ubuntu-dep

Add ca-certificates to our package Recommends

hack/make/ubuntu

@@ -111,6 +111,7 @@ EOF
 		    --depends lxc \
 		    --depends aufs-tools \
 		    --depends iptables \
+		    --deb-recommends ca-certificates \
 		    --description "$PACKAGE_DESCRIPTION" \
 		    --maintainer "$PACKAGE_MAINTAINER" \
 		    --conflicts lxc-docker-virtual-package \