including a default assets directory and instructions for how to use the bundled banner placeholders for the wordpress plugin repository

fixes #45

README.md

@@ -48,7 +48,9 @@ GNU General Public License for more details.
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 
-## A Note About Licensing
+## Important Notes
+
+### Licensing
 
 The WordPress Plugin Boilerplate is licensed under the GPL2+ or later; however, if you opt to use third-party frameworks
 such as [Bootstrap](http://twitter.github.io/bootstrap/) in your work, then you should be aware of this:
@@ -56,3 +58,26 @@ such as [Bootstrap](http://twitter.github.io/bootstrap/) in your work, then you
 > The most likely occurrence of this issue is with Themes developed using Twitter Bootstrap. When reviewing such Themes, please be sure to check that, if the Theme is licensed under GPL, that the license specifies either unversioned GPL, or GPLv3.0.
 
 For reference, [here's the full conversation](http://make.wordpress.org/themes/2013/03/04/licensing-note-apache-and-gpl/).
+
+## Assets
+
+The assets directory provides two files that are used to represent plugin header images.
+
+When committing your work to the WordPress Plugin Repository, these files should reside in their own `assets` directory, not in the root of the plugin. The initaly repository will contain three directories:
+
+1. `branches`
+2. `tags`
+3. `trunk`
+
+You'll need to add an `assets` directory into the root of the repository. So the final directory structure should include *four* directories:
+
+1. `assets`
+2. `branches`
+3. `tags`
+4. `trunk`
+
+Next, copy the contents of the `assets` directory that are bundled with the Boilerplate into the root of the repository. This is how the WordPress Plugin Repository will retrieving the plugin header image.
+
+Of course, you'll want to customize the header images from the place holders that are provided with the boilerplate.
+
+For more, in-depth information about this, read [this post](http://make.wordpress.org/plugins/2012/09/13/last-december-we-added-header-images-to-the/) by Otto.