Minor fix to CheckForDeprecatedImages(); skip image aliases too,

although need to come back to this once I figure out what the right
thing to do is.

db/Experiment.pm.in

@@ -6590,8 +6590,9 @@ sub CheckForDeprecatedImages($$$)
 	    }
 	}
 	# Skip anything that looks like an OSID instead of an image.
+	# XXX Need to deal with image aliases.
 	next
-	    if (!defined($image->image()));
+	    if (! $image->isImage());
 	
 	my $deprecated = 0;
 	my $iserror    = 0;

db/OSImage.pm.in

@@ -153,6 +153,7 @@ sub Lookup($$;$$)
 sub image($)		{ return $_[0]->{'IMAGE'}; }
 sub osinfo($)		{ return $_[0]->{'OSINFO'}; }
 sub temphash($)		{ return $_[0]->{'HASH'}; }
+sub isImage($)          { return defined($_[0]->image()) ? 1 : 0; }
 sub isImageAlias($)	{ return 0; }
 
 # Break circular references to avoid exit errors.
@@ -1527,6 +1528,7 @@ sub gid($)	    { return $_[0]->{'ALIAS'}->{'gid'}; }
 sub gid_idx($)	    { return $_[0]->{'ALIAS'}->{'gid_idx'}; }
 sub uuid($)	    { return $_[0]->{'ALIAS'}->{'uuid'}; }
 sub imagelist($)    { return values(%{ $_[0]->{'IMAGES'} }); }
+sub isImage($)      { return 0; }
 sub isImageAlias($) { return 1; }
 sub IsGeneric($)    { return 0; }
 sub mfs($)          { return 0; }