Optimize tests by avoiding reload of tokenizers

Change-Id: Ia70dab59fc3cfe5e47a1540724336214addb824e
diff --git a/token_writer.go b/token_writer.go
index 11179d3..bccb1bd 100644
--- a/token_writer.go
+++ b/token_writer.go
@@ -89,7 +89,7 @@
 
 	// Collect sentence positions and maybe sentence boundaries
 	if flags&SENTENCE_POS != 0 {
-		tw.SentenceEnd = func(offset int) {
+		tw.SentenceEnd = func(_ int) {
 
 			// Add end position of last token to sentence boundary
 			// TODO: This only works if token positions are taking into account