switch to circleci instead of travis-ci

.circleci/config.yml

@@ -0,0 +1,50 @@
+# Javascript Node CircleCI 2.0 configuration file
+#
+# Check https://circleci.com/docs/2.0/language-javascript/ for more details
+#
+version: 2
+jobs:
+  build:
+    docker:
+      # specify the version you desire here
+      - image: circleci/node:7.10
+
+      # Specify service dependencies here if necessary
+      # CircleCI maintains a library of pre-built images
+      # documented at https://circleci.com/docs/2.0/circleci-images/
+      # - image: circleci/mongo:3.4.4
+
+    working_directory: ~/Prebid.js
+
+    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: npm install
+
+      - save_cache:
+          paths:
+            - node_modules
+          key: v1-dependencies-{{ checksum "package.json" }}
+
+      - run: sudo npm install -g gulp
+      # Download and run BrowserStack local
+      - run:
+          name : Download BrowserStack Local binary and start it.
+          command : |
+            # Download the browserstack binary file
+            wget "https://www.browserstack.com/browserstack-local/BrowserStackLocal-linux-x64.zip"
+            # Unzip it
+            unzip BrowserStackLocal-linux-x64.zip
+            # Run the file with user's access key
+            ./BrowserStackLocal ${BROWSERSTACK_ACCESS_KEY} &
+      # run tests!
+      - run: 
+          name: BrowserStack testing
+          command: gulp test --browserstack

README.md

@@ -1,4 +1,4 @@
-[![Build Status](https://travis-ci.org/prebid/Prebid.js.svg?branch=master)](https://travis-ci.org/prebid/Prebid.js)
+[![Build Status](https://circleci.com/gh/prebid/Prebid.js.svg?style=svg)](https://circleci.com/gh/prebid/Prebid.js)
 [![Percentage of issues still open](http://isitmaintained.com/badge/open/prebid/Prebid.js.svg)](http://isitmaintained.com/project/prebid/Prebid.js "Percentage of issues still open")
 [![Average time to resolve an issue](http://isitmaintained.com/badge/resolution/prebid/Prebid.js.svg)](http://isitmaintained.com/project/prebid/Prebid.js "Average time to resolve an issue")
 [![Code Climate](https://codeclimate.com/github/prebid/Prebid.js/badges/gpa.svg)](https://codeclimate.com/github/prebid/Prebid.js)