Fix typo in index.html

'differnet' to 'different'

Author: dougshamoo

demo/index.html

@@ -89,7 +89,7 @@ <h1>UI-Calendar</h1>
                         <h3>What?</h3>
 
                         <p>Attach Angular objects to a calendar.</p>
-                        <p>Show the data binding between two differnet calendars using the same event sources.</p>
+                        <p>Show the data binding between two different calendars using the same event sources.</p>
 
                         <h3>Why?</h3>