command: "lsinfo" and "readcomments" allowed for remote files

src/SongUpdate.cxx

@@ -132,3 +132,17 @@ Song::UpdateFileInArchive()
 	tag = tag_builder.Commit();
 	return true;
 }
+
+bool
+Song::UpdateStream()
+{
+	assert(!IsFile());
+
+	TagBuilder tag_builder;
+	if (!tag_stream_scan(uri, full_tag_handler, &tag_builder))
+		return false;
+
+	delete tag;
+	tag = tag_builder.Commit();
+	return true;
+}