use only ID name for DOM (zenorocha#431)

Nathan · zenorocha · commit f960b0d20a1b · 2017-06-30T15:52:07.000-03:00
diff --git a/readme.md b/readme.md
@@ -149,7 +149,7 @@ For use in Bootstrap Modals or with any other library that changes the focus you
 
 ```js
 new Clipboard('.btn', {
-    container: document.getElementById('#modal')
+    container: document.getElementById('modal')
 });
 ```
 
