Merge pull request #2301 from fgrehm/document-remote-shell-provisioner

website/docs: document remote shell provisioner

website/docs/source/v2/provisioning/shell.html.md

@@ -24,8 +24,8 @@ is required:
   remote machine. See the [inline scripts](#inline-scripts) section below
   for more information.
 
-* `path` (string) - Path to a shell script to upload and execute, relative
-  to the project Vagrantfile.
+* `path` (string) - Path to a shell script to upload and execute. It can be a
+  script relative to the project Vagrantfile or a remote script (like a [gist](http://gist.github.com)).
 
 The remainder of the available options are optional:
 
@@ -102,6 +102,15 @@ Relative paths, such as above, are expanded relative to the location
 of the root Vagrantfile for your project. Absolute paths can also be used,
 as well as shortcuts such as `~` (home directory) and `..` (parent directory).
 
+If you use a remote script as part of your provisioning process, you can pass in
+its URL as the `path` argument as well:
+
+```ruby
+Vagrant.configure("2") do |config|
+  config.vm.provision "shell", path: "https://example.com/provisioner.sh"
+end
+```
+
 ## Script Arguments
 
 You can parameterize your scripts as well like any normal shell script.