Rivington: Update the description

rivington/sass/style-child-theme.scss

@@ -3,7 +3,7 @@ Theme Name: Rivington
 Theme URI: https://github.com/Automattic/themes/tree/master/rivington
 Author: Automattic
 Author URI: https://automattic.com/
-Description: A design system for WordPress sites built with Gutenberg.
+Description: Rivington is a robust theme designed for single property real estate.
 Requires at least: WordPress 4.9.6
 Version: 1.0.0
 License: GNU General Public License v2 or later

rivington/style-rtl.css

@@ -4,7 +4,7 @@ Theme Name: Rivington
 Theme URI: https://github.com/Automattic/themes/tree/master/rivington
 Author: Automattic
 Author URI: https://automattic.com/
-Description: A design system for WordPress sites built with Gutenberg.
+Description: Rivington is a robust theme designed for single property real estate.
 Requires at least: WordPress 4.9.6
 Version: 1.0.0
 License: GNU General Public License v2 or later

rivington/style.css

@@ -4,7 +4,7 @@ Theme Name: Rivington
 Theme URI: https://github.com/Automattic/themes/tree/master/rivington
 Author: Automattic
 Author URI: https://automattic.com/
-Description: A design system for WordPress sites built with Gutenberg.
+Description: Rivington is a robust theme designed for single property real estate.
 Requires at least: WordPress 4.9.6
 Version: 1.0.0
 License: GNU General Public License v2 or later