refactored JS:

- moved from global namespace into anonymous function
- as onclick has no direct access to the zerobin methods, the events are
now bound in the init() method via bindEvents()
- to simplify maintenance, the functions were wrapped into 3 objects:
zerobin (display logic, event handling), filter (compression,
encryption) and helper (stateless utilities)
- some CSS and template adjustements were also done

css/zerobin.css

@@ -65,7 +65,6 @@ h3 {
 }   
 
 #aboutbox { 
-	font-size: 1.2em;
 	color: #94a3b4; 
 	padding: 4px 8px 4px 16px;
 	position: relative;