Update README.md file

Author: joshua-larsen

README.md

@@ -11,7 +11,7 @@
 [Theme Store submission](#theme-store-submission) |
 [License](#license)
 
-Dawn represents a HTML-first, JavaScript-only-as-needed approach to theme development. It's Shopify's first source available theme with performance, flexibility, and [Online Store 2.0 features](https://www.shopify.com/partners/blog/shopify-online-store) built-in and acts as a reference for building Shopify themes!
+Dawn represents a HTML-first, JavaScript-only-as-needed approach to theme development. It's Shopify's first source available theme with performance, flexibility, and [Online Store 2.0 features](https://www.shopify.com/partners/blog/shopify-online-store) built-in and acts as a reference for building Shopify themes.
 
 * **Web-native in its purest form:** Themes run on the [evergreen web](https://www.w3.org/2001/tag/doc/evergreen-web/). We leverage the latest web browsers to their fullest, while maintaining support for the older ones through progressive enhancement—not polyfills.
 * **Lean, fast, and reliable:** Functionality and design defaults to “no” until it meets this requirement. Code ships on quality. Themes must be built with purpose. They shouldn’t support each and every feature in Shopify.