Laravel 5.6 updates

Travis config update

Removed HHVM script as Laravel no longer support HHVM after releasing 5.3

.travis.yml

@@ -3,9 +3,8 @@ language: php
 
 # Versions of PHP you want your project run with.
 php:
-  - 5.5
-  - 5.6
-  - hhvm
+  - 7.1
+  - 7.2
 
 # Commands to be run before your environment runs.
 before_script:
@@ -20,7 +19,6 @@ script: phpunit
 matrix:
   allow_failures:
     - php: 5.5
-    - php: hhvm
   fast_finish: true
 
 # Customize when the notification emails are sent.