[ghex] Update help LINGUAS

[Piotr Drąg <piotrdrag src gnome org>]

commit d6164406b326d7e4658a8d2f5eaf4276575c12e8
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Mon Mar 19 16:35:17 2018 +0100

    Update help LINGUAS

 help/LINGUAS |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/help/LINGUAS b/help/LINGUAS
index f940bd0..19c61ed 100644
--- a/help/LINGUAS
+++ b/help/LINGUAS
@@ -8,6 +8,7 @@ it
 ja
 ko
 oc
+pl
 pt_BR
 ru
 sl