add visual example

README.md

@@ -1,5 +1,7 @@
 ![Greenlock Logo](https://git.coolaj86.com/coolaj86/greenlock.js/raw/branch/master/logo/greenlock-1063x250.png "Greenlock Logo")
 
+!["Greenlock Function"](https://git.coolaj86.com/coolaj86/greenlock.js/raw/branch/master/logo/from-not-secure-to-secure-url-bar.png "from url bar showing not secure to url bar showing secure")
+
 Greenlock™ for Express.js
 =================
 Free SSL, Free Wildcard SSL, and Fully Automated HTTPS made dead simple<br>