Merge pull request #10250 from briancain/fix-old-box-url

Update old URL for box_url example

website/source/intro/getting-started/boxes.html.md

@@ -89,7 +89,7 @@ You may also specify the URL to a box directly using `config.vm.box_url`:
 ```ruby
 Vagrant.configure("2") do |config|
   config.vm.box = "hashicorp/precise64"
-  config.vm.box_url = "http://files.vagrantup.com/precise64.box"
+  config.vm.box_url = "https://vagrantcloud.com/hashicorp/precise64"
 end
 ```