repaired structure and config.yaml for nspawn and docker

Makefile

@@ -1,8 +1,14 @@
+DOCKER_IMAGE=ruby
+
 default: test
 
-build:
-	docker build -t ruby .
-	docker run -d ruby
+build-docker:
+	docker build -t $(DOCKER_IMAGE) . 
 
-test:
-	$(MAKE) -C tests $@
+test-nspawn:
+	MODULE=nspawn $(MAKE) -C tests test
+
+test-docker: build-docker
+	MODULE=docker URL=docker=$(DOCKER_IMAGE) $(MAKE) -C tests test
+
+test: test-nspawn test-docker