Update generic target

Author: sinn3r

lib/msf/core/exploit/http/server.rb

@@ -873,7 +873,7 @@ def js_property_spray
 						break;
 
 					case 'generic':
-						obj.title = data.substring(0, heapBlockSize-0x58);
+						obj.title = data.substring(0, (heapBlockSize-2)/2);
 						div_container.appendChild(obj);
 						break;