Add @ag_dubs to sinatra-core 👏 🎉 🎊 🎉

Author: Zachary Scott

AUTHORS.md

@@ -5,6 +5,7 @@ Sinatra was designed and developed by Blake Mizerany in California.
 * **Konstantin Haase** (maintainer)
 * **Zachary Scott**
 * **Katrina Owen**
+* **Ashley Williams**
 
 ### Alumni
 
@@ -74,4 +75,4 @@ Sinatra would not be possible:
 And last but not least:
 
 * [Frank Sinatra](http://www.sinatra.com/) (chairman of the board) for having so much class he
-  deserves a web-framework named after him.
+  deserves a web-framework named after him.