[gtranslator] Increase release number to unstable 3.31

[Daniel Garcia Moreno <danigm src gnome org>]

commit 9216e44d378537b64bdc39819f3c6c688e02378d
Author: Daniel García Moreno <danigm wadobo com>
Date:   Sat Nov 3 10:54:20 2018 +0100

    Increase release number to unstable 3.31

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index c178ece9..fa242b09 100644
--- a/meson.build
+++ b/meson.build
@@ -1,6 +1,6 @@
 project(
   'gtranslator', 'c',
-  version: '3.30.0',
+  version: '3.31.0',
   license: 'GPL3+',
   meson_version: '>= 0.46.0',
 )