release: prepare for 3.7.3

NEWS

+3.7.3
+=====
+
+Don't repeat background image assets for radio/checks
+Use a light noise texture for content-view backgrounds
+Add a style for OSD views and scrollbars
+Improve style for listbox views
+Remove GtkViewport background color by default
+Improve style for dragged column-header buttons
+Update HighContrast icons
+Fix asymmetric borders in column-header buttons
+Fix coloring of GtkScale mark labels
+Fix GTK2 toolbar style for SWT applications
+Fix coloring of Eclipse tooltips
+Fix buggy rendering of menus in Opera
+
 3.7.2
 =====
 

configure.ac

 dnl Process this file with autoconf to produce a configure script.
 AC_PREREQ(2.53)
 
-AC_INIT([gnome-themes-standard], [3.7.2],
+AC_INIT([gnome-themes-standard], [3.7.3],
         [http://bugzilla.gnome.org/enter_bug.cgi?product=gnome-themes-standard])
 
 AM_INIT_AUTOMAKE([1.9 tar-ustar foreign dist-xz no-dist-gzip])