release: prepare for 3.5.90

NEWS

+3.5.90
+======
+
+Add a GTK2 version of Adwaita, based on the Bridge theme (Jack Gandy)
+New default wallpapers (Jakub Steiner)
+Improve metacity attached dialog styling (Florian Müllner)
+Improve custom theming for Nautilus (Lapo Calamandrei)
+Add generic theming support for selection-mode toolbar style classes
+Add generic theming support for in-app notifications
+Add generic theming support for suggested-action buttons
+Improve theming for GtkMenuButton
+
 3.5.5
 =====
 

configure.ac

 dnl Process this file with autoconf to produce a configure script.
 AC_PREREQ(2.53)
 
-AC_INIT([gnome-themes-standard], [3.5.5],
+AC_INIT([gnome-themes-standard], [3.5.90],
         [http://bugzilla.gnome.org/enter_bug.cgi?product=gnome-themes-standard])
 
 AM_INIT_AUTOMAKE([1.9 tar-ustar foreign dist-xz no-dist-gzip])