Integrate Browserstack tests into Travis CI build

Resolves #766

.travis.yml

@@ -11,3 +11,10 @@ before_install:
 
 script:
   - gulp run-tests
+
+addons:
+  browserstack:
+    username:
+      secure: "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"
+    access_key:
+      secure: "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"

browsers.json

@@ -119,6 +119,14 @@
     "device": null,
     "os": "Windows"
   },
+  "bs_chrome_56_mac_sierra": {
+    "base": "BrowserStack",
+    "os": "OS X",
+    "os_version": "Sierra",
+    "browser": "chrome",
+    "device": null,
+    "browser_version": "56.0"
+  },
   "bs_safari_9.1_mac_elcapitan": {
     "base": "BrowserStack",
     "os_version": "El Capitan",

gulpfile.js

@@ -92,7 +92,9 @@ gulp.task('test', function () {
   var browserArgs = helpers.parseBrowserArgs(argv).map(helpers.toCapitalCase);
 
   if (process.env.TRAVIS) {
-    browserArgs = ['Chrome_travis_ci'];
+    browserArgs = [
+      'bs_chrome_54_mac_sierra',
+    ];
   }
 
   if (argv.browserstack) {

karma.conf.js

@@ -19,8 +19,8 @@ module.exports = function (config) {
 
     // BrowserStack Config
     browserStack: {
-      username: process.env.BROWSERSTACK_USERNAME,
-      accessKey: process.env.BROWSERSTACK_KEY
+      username: process.env.BROWSERSTACK_USERNAME || process.env.BROWSERSTACK_USER,
+      accessKey: process.env.BROWSERSTACK_KEY || process.env.BROWSERSTACK_ACCESS_KEY
     },
 
     // define browsers