Add rsync'd folder configuration

Made the default disabled inline with previous releases.

README.md

@@ -25,6 +25,16 @@ vagrant ssh
 
 Start running Docker like you usually would!
 
+## Enable Rsync folder sync
+If you want to sync the current working directory via rsync edit the Vagrantfile and change this line:
+
+<pre>$rsync_folder_disabled = true</pre>
+
+to
+
+<pre>
+$rsync_folder_disabled = <b>false</b>
+</pre>
 ## Upgrading RancherOS Versions
 
 To upgrade the Vagrant box, refresh this repository from master.

Vagrantfile

@@ -1,6 +1,10 @@
 # -*- mode: ruby -*-
 # vi: set ft=ruby :
 
+# To enable rsync folder share change to false
+$rsync_folder_disabled = true
+
+
 # All Vagrant configuration is done below. The "2" in Vagrant.configure
 # configures the configuration version (we support older styles for
 # backwards compatibility). Please don't change it unless you know what
@@ -16,5 +20,10 @@ Vagrant.configure(2) do |config|
      vb.memory = "1024"
   end
 
-  config.vm.synced_folder ".", "/vagrant", disabled: true
+  # Disabling compression because OS X has an ancient version of rsync installed.
+  # Add -z or remove rsync__args below if you have a newer version of rsync on your machine.
+  config.vm.synced_folder ".", "/opt/rancher", type: "rsync",
+    rsync__exclude: ".git/", rsync__args: ["--verbose", "--archive", "--delete", "--copy-links"],
+    disabled: $rsync_folder_disabled
+
 end