Add make test task, use make in circle.yml

Author: wfleming

Diff for: Makefile

@@ -1,6 +1,9 @@
-.PHONY: image
+.PHONY: image test
 
 IMAGE_NAME ?= codeclimate/codeclimate-eslint
 
 image:
 	docker build --rm -t $(IMAGE_NAME) .
+
+test: image
+	docker run $(IMAGE_NAME) npm run test

Diff for: circle.yml

@@ -11,7 +11,7 @@ machine:
 
 test:
   override:
-    - docker build -t=$PRIVATE_REGISTRY/$CIRCLE_PROJECT_REPONAME:b$CIRCLE_BUILD_NUM .
+    - IMAGE_NAME="$PRIVATE_REGISTRY/$CIRCLE_PROJECT_REPONAME:b$CIRCLE_BUILD_NUM" make test
 
 deployment:
   registry: