[devhelp] NEWS file: start to write news for 3.29.1

[Sébastien Wilmet <swilmet src gnome org>]

commit 14871ec1eb062e823f7aa82bf78a59b8f1fecd8c
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sun Apr 1 21:54:57 2018 +0200

    NEWS file: start to write news for 3.29.1

 NEWS |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)
---
diff --git a/NEWS b/NEWS
index 0cfece3..17ed280 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,13 @@
+News in 3.29.1, 2018-xx-yy (not yet released)
+--------------------------
+* Move library to its own directory, to separate it from the app. Some source
+  files needed to be split in two.
+* Switch build system from Autotools to Meson (and remove Autotools).
+* Update the license from GPLv2+ to GPLv3+.
+* AppData: update screenshots.
+* A few other small improvements.
+* Translation updates.
+
 News in 3.28.0, 2018-03-10
 --------------------------
 * Improve default GSettings values.