[gnome-2048] Add Language headers to po files

[Piotr Drąg <piotrdrag src gnome org>]

commit 825d1a56d573b9e60523fc6813828f7a8394a88f
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Sun Jul 17 18:29:25 2016 +0200

    Add Language headers to po files
    
    Future versions of gettext will fail if this header is missing.

 po/ca.po       |    2 +-
 po/es.po       |    2 +-
 po/sl.po       |    2 +-
 po/sr latin po |    2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/po/ca.po b/po/ca.po
index fad8433..6780daf 100644
--- a/po/ca.po
+++ b/po/ca.po
@@ -14,7 +14,7 @@ msgstr ""
 "PO-Revision-Date: 2015-03-22 11:38-0500\n"
 "Last-Translator: Jordi Mas i Hernàndez <jmas softcatala org>\n"
 "Language-Team: ca_ES <tradgnome softcatala net>\n"
-"Language: \n"
+"Language: ca\n"
 "MIME-Version: 1.0\n"
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"
diff --git a/po/es.po b/po/es.po
index 1979672..aac2f31 100644
--- a/po/es.po
+++ b/po/es.po
@@ -14,7 +14,7 @@ msgstr ""
 "PO-Revision-Date: 2016-04-07 12:50+0200\n"
 "Last-Translator: Daniel Mustieles <daniel mustieles gmail com>\n"
 "Language-Team: Español; Castellano <gnome-es-list gnome org>\n"
-"Language: \n"
+"Language: es\n"
 "MIME-Version: 1.0\n"
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"
diff --git a/po/sl.po b/po/sl.po
index 23ad166..3fb3676 100644
--- a/po/sl.po
+++ b/po/sl.po
@@ -13,7 +13,7 @@ msgstr ""
 "PO-Revision-Date: 2015-02-24 19:03+0100\n"
 "Last-Translator: Matej Urbančič <mateju svn gnome org>\n"
 "Language-Team: Slovenian <sl li org>\n"
-"Language: Slovenian\n"
+"Language: sl\n"
 "MIME-Version: 1.0\n"
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"
diff --git a/po/sr latin po b/po/sr latin po
index 79624cf..03099ca 100644
--- a/po/sr latin po
+++ b/po/sr latin po
@@ -11,7 +11,7 @@ msgstr ""
 "PO-Revision-Date: 2016-02-21 07:12+0200\n"
 "Last-Translator: Miroslav Nikolić <miroslavnikolic rocketmail com>\n"
 "Language-Team: Serbian <gnom prevod org>\n"
-"Language: sr\n"
+"Language: sr@latin\n"
 "MIME-Version: 1.0\n"
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"