Merge pull request #677 from ExE-Boss/travis/use-xenial

chore(travis): Use Xenial

Author: rkeithhill

.travis.yml

@@ -13,12 +13,12 @@ jobs:
   include:
     - stage: linux
       os: linux
-      dist: trusty
+      dist: xenial
       sudo: false
       addons:
         apt:
           sources:
-            - sourceline: deb [arch=amd64] https://packages.microsoft.com/ubuntu/14.04/prod trusty main
+            - sourceline: deb [arch=amd64] https://packages.microsoft.com/ubuntu/16.04/prod xenial main
               key_url: https://packages.microsoft.com/keys/microsoft.asc
           packages:
             - powershell