Added extraction method for documents in archives

Change-Id: Id4ea7d9801a5750c77f81a2251d389adb6e06d31
diff --git a/t/multiple_archives.t b/t/multiple_archives.t
index 7865101..1da4e9d 100644
--- a/t/multiple_archives.t
+++ b/t/multiple_archives.t
@@ -60,7 +60,7 @@
 my $dir = tempdir(CLEANUP => 1);
 {
   local $SIG{__WARN__} = sub {};
-  ok($archive->extract($list[0], $dir), 'Wrong path');
+  ok($archive->extract_text($list[0], $dir), 'Wrong path');
 };
 
 ok(-d catdir($dir, 'WPD15'), 'Test corpus directory exists');