Try out circleci workflow

Signed-off-by: Daniel Nephin <dnephin@docker.com>

circle.yml

@@ -1,14 +1,11 @@
 version: 2
+
 jobs:
-  build:
+
+  lint:
     working_directory: /work
-    docker:
-      - image: docker:17.05
-    parallelism: 4
+    docker: [{image: 'docker:17.05'}]
     steps:
-      - run:
-          name: "Install Git and SSH"
-          command: apk add -U git openssh
       - checkout
       - setup_remote_docker
       - run:
@@ -16,40 +13,69 @@ jobs:
       - run:
           name: "Lint"
           command: |
-            if [ "$CIRCLE_NODE_INDEX" != "0" ]; then exit; fi
             dockerfile=dockerfiles/Dockerfile.lint
             echo "COPY . ." >> $dockerfile
             docker build -f $dockerfile --tag cli-linter .
             docker run cli-linter
+
+  cross:
+    working_directory: /work
+    docker: [{image: 'docker:17.05'}]
+    steps:
+      - checkout
+      - setup_remote_docker
       - run:
           name: "Cross"
           command: |
-            if [ "$CIRCLE_NODE_INDEX" != "1" ]; then exit; fi
             dockerfile=dockerfiles/Dockerfile.cross
             echo "COPY . ." >> $dockerfile
             docker build -f $dockerfile --tag cli-builder .
             docker run --name cross cli-builder make cross
             docker cp cross:/go/src/github.com/docker/cli/build /work/build
+      - store_artifacts:
+          path: /work/build
+
+  test:
+    working_directory: /work
+    docker: [{image: 'docker:17.05'}]
+    steps:
+      - checkout
+      - setup_remote_docker
       - run:
           name: "Unit Test with Coverage"
           command: |
-            if [ "$CIRCLE_NODE_INDEX" != "2" ]; then exit; fi
             dockerfile=dockerfiles/Dockerfile.dev
             echo "COPY . ." >> $dockerfile
             docker build -f $dockerfile --tag cli-builder .
             docker run --name test cli-builder make test-coverage
+
+      - run:
+          name: "Upload to Codecov"
+          command: |
             docker cp test:/go/src/github.com/docker/cli/coverage.txt coverage.txt
             apk add -U bash curl
             curl -s https://codecov.io/bash | bash
+
+  validate:
+    working_directory: /work
+    docker: [{image: 'docker:17.05'}]
+    steps:
+      - checkout
+      - setup_remote_docker
       - run:
           name: "Validate Vendor, Docs, and Code Generation"
           command: |
-            if [ "$CIRCLE_NODE_INDEX" != "3" ]; then exit; fi
             dockerfile=dockerfiles/Dockerfile.dev
             echo "COPY . ." >> $dockerfile
             rm -f .dockerignore # include .git
             docker build -f $dockerfile --tag cli-builder .
             docker run cli-builder make -B vendor compose-jsonschema manpages yamldocs
 
-      - store_artifacts:
-          path: /work/build
+workflows:
+  version: 2
+  ci:
+    jobs:
+      - lint
+      - cross
+      - test
+      - validate