macosx: slightly change scrolling behavior of the credits to the way we do it in Lunettes

Basically, we starting scrolling at the beginning, if the window gets reopened and jump back to top once scrolling reached the end of the list.

modules/gui/macosx/about.m

 /*****************************************************************************
  * about.m: MacOS X About Panel
  *****************************************************************************
- * Copyright (C) 2001-2007 the VideoLAN team
+ * Copyright (C) 2001-2009 the VideoLAN team
  * $Id$
  *
  * Authors: Derk-Jan Hartman <thedj@users.sourceforge.net>
@@ -112,6 +112,7 @@ static VLAboutBox *_o_sharedInstance = nil;
  
     /* Show the window */
     b_restart = YES;
+    [o_credits_textview scrollPoint:NSMakePoint( 0, 0 )];
     [o_about_window makeKeyAndOrderFront: nil];
 }
 
@@ -134,7 +135,7 @@ static VLAboutBox *_o_sharedInstance = nil;
     if( b_restart )
     {
         /* Reset the starttime */
-        i_start = [NSDate timeIntervalSinceReferenceDate] + 3.0;
+        i_start = [NSDate timeIntervalSinceReferenceDate] + 5.0;
         f_current = 0;
         f_end = [o_credits_textview bounds].size.height - [o_credits_scrollview bounds].size.height;
         b_restart = NO;
@@ -151,6 +152,7 @@ static VLAboutBox *_o_sharedInstance = nil;
         /* If at end, restart at the top */
         if( f_current >= f_end )
         {
+            [o_credits_textview scrollPoint:NSMakePoint( 0, 0 )];
             b_restart = YES;
         }
     }