build: bump version to 1.9.0

The start of the new development series.

NEWS.org

@@ -1,6 +1,17 @@
 #+STARTUP:showall
 * NEWS (user visible changes & bigger non-visible ones)
 
+* 1.9 (unreleased development version)
+
+*** building
+
+    - the autotools build (which was deprecated since 1.8) has now been removed.
+      we thank it for its services since 2008. We continue with ~meson~.
+
+      However, we still have ~autogen.sh~ and a ~Makefile~ which can be helpful for
+      driving ~meson~-based builds. Think of the ~Makefile~ as a convenient place to
+      put common action for which I always forget the ~meson~ incantation.**
+
 * 1.8 (released on June 25, 2022)
 
   (there are some changes in the installation procedure compared to 1.6.x; see

meson.build

@@ -18,7 +18,7 @@
 # project setup
 #
 project('mu', ['c', 'cpp'],
-	version: '1.8.9',
+	version: '1.9.0',
 	meson_version: '>= 0.52.0', # debian 10
 	license: 'GPL-3.0-or-later',
 	default_options : [