Merge scrape branch:

Automatically scrape trackers as needed.
  If tracker supplies a trackerid then use it (untested).
  Use tracker's min interval, clamped to the same range as interval.
  Show total completed downloads in the MacOS X frontend.

macosx/English.lproj/InfoWindow.nib/classes.nib

@@ -19,6 +19,7 @@
             LANGUAGE = ObjC; 
             OUTLETS = {
                 fCommentView = NSTextView; 
+                fCompletedFromTrackerField = NSTextField; 
                 fConnectedPeersField = NSTextField; 
                 fCreatorField = NSTextField; 
                 fDataLocationField = NSTextField;