Add gtksourceview3

The repository had gtk3 and gtksourceview2, but not gtksourceview3.

This is my first package so I am not totally sure everything is done correctly. I had it working successfully for w64 static libraries.

src/gtksourceview3-1-fixes.patch

@@ -0,0 +1,33 @@
+This file is part of MXE. See LICENSE.md for licensing information.
+
+From 6837c9e5c97212b030f4aa0f343b5053f5a3bb40 Mon Sep 17 00:00:00 2001
+From: Louis Gesbert <louis.gesbert@ocamlpro.com>
+Date: Wed, 16 Oct 2019 14:24:45 +0200
+Subject: [PATCH] Rename "DllMain"
+
+---
+ gtksourceview/gtksourceview-init.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/gtksourceview/gtksourceview-init.c b/gtksourceview/gtksourceview-init.c
+index c40e319..c9b0613 100644
+--- a/gtksourceview/gtksourceview-init.c
++++ b/gtksourceview/gtksourceview-init.c
+@@ -150,12 +150,12 @@ gtksourceview_shutdown (void)
+ 
+ #if defined (G_OS_WIN32)
+ 
+-BOOL WINAPI DllMain (HINSTANCE hinstDLL,
++BOOL WINAPI gtksourceview_DllMain (HINSTANCE hinstDLL,
+ 		     DWORD     fdwReason,
+ 		     LPVOID    lpvReserved);
+ 
+ BOOL WINAPI
+-DllMain (HINSTANCE hinstDLL,
++gtksourceview_DllMain (HINSTANCE hinstDLL,
+ 	 DWORD     fdwReason,
+ 	 LPVOID    lpvReserved)
+ {
+-- 
+2.11.0
+

src/gtksourceview3.mk

@@ -0,0 +1,27 @@
+# This file is part of MXE. See LICENSE.md for licensing information.
+
+PKG             := gtksourceview3
+$(PKG)_WEBSITE  := https://projects.gnome.org/gtksourceview/
+$(PKG)_DESCR    := GTKSourceView
+$(PKG)_IGNORE   :=
+$(PKG)_VERSION  := 3.24.11
+$(PKG)_CHECKSUM := 691b074a37b2a307f7f48edc5b8c7afa7301709be56378ccf9cc9735909077fd
+$(PKG)_SUBDIR   := gtksourceview-$($(PKG)_VERSION)
+$(PKG)_FILE     := gtksourceview-$($(PKG)_VERSION).tar.xz
+$(PKG)_URL      := https://download.gnome.org/sources/gtksourceview/$(call SHORT_PKG_VERSION,$(PKG))/$($(PKG)_FILE)
+$(PKG)_DEPS     := cc gtk3 libxml2
+
+define $(PKG)_UPDATE
+    $(WGET) -q -O- 'https://gitlab.gnome.org/GNOME/gtksourceview/tags?&search=GTKSOURCEVIEW_3' | \
+    $(SED) -n "s,.*<a [^>]\+>GTKSOURCEVIEW_\(3_[0-9_]\+\)<.*,\1,p" | \
+    $(SED) "s,_,.,g;" | \
+    grep -v '^3\.9[0-9]\.' | \
+    head -1
+endef
+
+define $(PKG)_BUILD
+    cd '$(BUILD_DIR)' && '$(SOURCE_DIR)/configure' \
+        $(MXE_CONFIGURE_OPTS)
+    $(MAKE) -C '$(BUILD_DIR)' -j '$(JOBS)' $(MXE_DISABLE_CRUFT)
+    $(MAKE) -C '$(BUILD_DIR)' -j 1 install $(MXE_DISABLE_CRUFT)
+endef