Adding README.md for example_box.

.gitignore

@@ -4,6 +4,7 @@ Gemfile.lock
 azure.box
 Vagrantfile
 !example_box/Vagrantfile
+!example_box/README.md
 babu
 example_box/
 *.rdp

example_box/README.md

@@ -0,0 +1,9 @@
+# Vagrant Azure Example Box
+
+This directory contains the sample contents of a box for `azure` provider. Build this into a box using:
+
+```
+C:\> bsdtar -cvzf azure.box metadata.json Vagrantfile
+```
+
+You can add any defaults supported by the ```azure``` provider to the `Vagrantfile` in your box and Vagrant's built-in merging system will set them as defaults. Users can override these defaults in their own Vagrantfiles.