Disallow name="" in Content-Disposition header.

Jon Jensen noticed that the last commit (b29f34f) introduced a new
problem by relaxing the constraint a little too much and allowing
empty strings. This patch by Mike Heins goes back to requiring at
least one character, while still allowing 0.

lib/Vend/Server.pm

@@ -478,7 +478,7 @@ sub parse_multipart {
 			}
 
 #::logDebug("Content-Disposition: " .  $header{'Content-Disposition'});
-			my($param)= $header{'Content-Disposition'}=~/ name="?([^\";]*)"?/;
+			my($param)= $header{'Content-Disposition'}=~/ name="?([^\";]+)"?/;
 
 			# Bug:  Netscape doesn't escape quotation marks in file names!!!
 			my($filename) = $header{'Content-Disposition'}=~/ filename="?([^\";]*)"?/;