gtkmm3: bump to version 3.20.0

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/gtkmm3/gtkmm3.hash

@@ -1,2 +1,2 @@
-# From http://ftp.gnome.org/pub/GNOME/sources/gtkmm/3.18/gtkmm-3.18.0.sha256sum
-sha256	829fa113daed74398c49c3f2b7672807f58ba85d0fa463f5bc726e1b0138b86b	gtkmm-3.18.0.tar.xz
+# From http://ftp.gnome.org/pub/GNOME/sources/gtkmm/3.20/gtkmm-3.20.0.sha256sum
+sha256	f021573f870df8a0b40ba37a7864c37be517c7a88cc957a193dbab28449b028a	gtkmm-3.20.0.tar.xz

package/gtkmm3/gtkmm3.mk

@@ -4,7 +4,7 @@
 #
 ################################################################################
 
-GTKMM3_VERSION_MAJOR = 3.18
+GTKMM3_VERSION_MAJOR = 3.20
 GTKMM3_VERSION = $(GTKMM3_VERSION_MAJOR).0
 GTKMM3_SOURCE = gtkmm-$(GTKMM3_VERSION).tar.xz
 GTKMM3_SITE = http://ftp.gnome.org/pub/gnome/sources/gtkmm/$(GTKMM3_VERSION_MAJOR)