[pybliographer] l10n: Generate plural forms into the .pot file

[Germán Poo-Caamaño <gpoo src gnome org>]

commit efd437e21f6442c62d501b732091e890ef604a70
Author: Germán Poo-Caamaño <gpoo gnome org>
Date:   Thu Mar 29 19:21:21 2018 -0300

    l10n: Generate plural forms into the .pot file
    
    Set the proper keyword for gettex to handle our alias
    for ngettext (_n).
    
    https://stackoverflow.com/questions/711637/generating-plural-forms-into-a-pot-file
    
    Fixes https://bugzilla.gnome.org/show_bug.cgi?id=794821

 po/Makevars |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/po/Makevars b/po/Makevars
index 99d5a20..f23b09e 100644
--- a/po/Makevars
+++ b/po/Makevars
@@ -10,7 +10,8 @@ top_builddir = ..
 # These options get passed to xgettext.
 XGETTEXT_OPTIONS = --from-code=UTF-8 --keyword=_ --keyword=N_ \
     --keyword=C_:1c,2 --keyword=NC_:1c,2 \
-    --keyword=g_dngettext:2,3 --add-comments
+    --keyword=g_dngettext:2,3 --keyword=_n:1,2 \
+    --add-comments
 
 # This is the copyright holder that gets inserted into the header of the
 # $(DOMAIN).pot file.  Set this to the copyright holder of the surrounding