README.md in sprite-0.1.6 vs README.md in sprite-0.1.7

@@ -77,10 +77,11 @@
   - `public_path:` defines the root folder where static assets live (defaults to `public/`)
   - `sprites_class:` defines the class name that gets added to all sprite stylesheet rules (defaults to `sprites`)
   - `default_format:` defines the default file image format of the generated files. (defaults to `png`)
   - `default_spacing:` defines the default pixel spacing between sprites (defaults to 0)
   - `class_separator:` used to generated the class name by separating the image name and sprite name (defaults to `-`)
-
+  - `add_datestamps`: whether or not to add datestamps to the generated background image urls. this will allow proper cache versioning (defaults to `true`)
+  
 * `images:` section provides an array of configurations which define which image files are built, and where they get their sprites from. each image setup provides the following config options:
   - `name:` name of image (required)
   - `sources:` defines a list of source image filenames to build the target image from (required). They are parsed by <code>Dir.glob</code>
   - `align:` defines the composite gravity type, horizontal or vertical. (defaults to `vertical`)
   - `spaced_by:` spacing (in pixels) between the combined images. (defaults to `0`)