ci(build): add circleci config for build (#24)

closes #1

.circleci/config.yml

@@ -0,0 +1,33 @@
+defaults: 
+  docker: &docker
+    - image: 'circleci/node:8-browsers'
+
+version: 2
+jobs:
+  build:
+    docker: *docker
+    working_directory: ~/repo
+
+    steps:
+      - checkout
+
+      - restore_cache:
+          keys:
+          - v1-dependencies-{{ checksum "yarn.lock" }}
+          # 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 "yarn.lock" }}
+
+      - run: yarn build
+
+workflows:
+  version: 2
+  build:
+    jobs:
+      - build

README.md

@@ -1,4 +1,5 @@
 # @angular-redux
+[![CircleCI](https://circleci.com/gh/angular-redux/platform/tree/master.svg?style=svg)](https://circleci.com/gh/angular-redux/platform/tree/master)
 
 [Redux](https://redux.js.org/) bindings for [Angular](https://angular.io/) applications.