add guidelines for fonts and icons.

README.md

-This is a sample HTML/CSS/JavaScript that strictly follows our naming convention.
+This is a guideline of the HTML/CSS/Javascript. It also includes an example that strictly follows this guideline.
 
 # CSS
 
@@ -35,3 +35,11 @@ Here are some guidelines of the usage of JavaScript :
 
 * Never try tricky things with JavaScript in Form appearance, that may easily break browser compatibility.
 * JQuery is available. Feel free to use it as much as possible for better readability and maintainability of the code.
+
+# Fonts
+
+Use [Google Fonts](https://fonts.google.com/) (or any web fonts available on CDN) for better performance.
+
+# Icons
+
+Use [Font Awesome](http://fontawesome.io/) (or any iconic fonts available on CDN) for better performance.