Add CircleCI config

Author: JedWatson

.circleci/config.yml

@@ -0,0 +1,37 @@
+# Javascript Node CircleCI 2.0 configuration file
+#
+# Check https://circleci.com/docs/2.0/language-javascript/ for more details
+#
+version: 2
+jobs:
+  build:
+    docker:
+      - image: circleci/node:8.4
+
+    working_directory: ~/repo
+
+    steps:
+      - checkout
+
+      # Download and cache dependencies
+      - restore_cache:
+          keys:
+          - v1-dependencies-{{ checksum "package.json" }}
+          # fallback to using the latest cache if no exact match is found
+          - v1-dependencies-
+
+      - run: yarn install
+
+      - save_cache:
+          paths:
+            - node_modules
+          key: v1-dependencies-{{ checksum "package.json" }}
+
+      # Start the examples server so that Cypress can run against them
+      - run: yarn start
+      # Install vxfb for Cypress
+      - run: yarn add xvfb
+      # Run eslint
+      - run: yarn lint
+      # Run tests
+      - run: yarn test