This will activate the WordPress Plugin Boilerplate. Because the Boilerplate has no real functionality, nothing will be added to WordPress; however, this demonstrates exactly how your plugin should behave as you're working with it.
> 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.
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.