Clean code to take advantage of new L5.5 features, bring back some dusk

tests now we can use headless chrome.

Squashed commit of the following:

commit d32d6e9dca7eb26303435c738f7c547e5009b86b
Author: Jonny Barnes <jonny@jonnybarnes.uk>
Date:   Wed Sep 6 14:43:52 2017 +0100

    Add dusk tests, cleanup other parts of travis.yml

commit 7633b407ee222a3f4a222f889f23acf4b5549c22
Author: Jonny Barnes <jonny@jonnybarnes.uk>
Date:   Wed Sep 6 14:38:39 2017 +0100

    I think dusk works locally with headless chrome now, just struggling on my slow laptop

commit fcbc83bb0a53ac046c1af09e8caf296799a940ef
Author: Jonny Barnes <jonny@jonnybarnes.uk>
Date:   Tue Sep 5 15:47:39 2017 +0100

    Get latest package versions and remove un-needed service provider entries

tests/DuskTestCase.php

@@ -3,6 +3,7 @@
 namespace Tests;
 
 use Laravel\Dusk\TestCase as BaseTestCase;
+use Facebook\WebDriver\Chrome\ChromeOptions;
 use Facebook\WebDriver\Remote\RemoteWebDriver;
 use Facebook\WebDriver\Remote\DesiredCapabilities;
 
@@ -18,7 +19,7 @@ abstract class DuskTestCase extends BaseTestCase
      */
     public static function prepare()
     {
-        //static::startChromeDriver();
+        static::startChromeDriver();
     }
 
     /**
@@ -28,8 +29,18 @@ abstract class DuskTestCase extends BaseTestCase
      */
     protected function driver()
     {
+        $desiredCapabilities = DesiredCapabilities::chrome();
+
+        $options = new ChromeOptions();
+        $options->addArguments([
+            'headless',
+            'disable-gpu'
+        ]);
+
+        $desiredCapabilities->setCapability(ChromeOptions::CAPABILITY, $options);
+
         return RemoteWebDriver::create(
-            'http://localhost:9515', DesiredCapabilities::phantomjs()
+            'http://localhost:9515', $desiredCapabilities
         );
     }
 }