Define INITGUID only for mingw.org compiler

Defining INITGUID causes a build failure with mingw-w64 > r5589.

https://bugzilla.gnome.org/show_bug.cgi?id=699673

(cherry picked from commit 6a71820ff399b32c4a95e7b17979513783c4e052)
gtkdialog - more informative warning when ordering unexisting response_id
(cherry picked from commit 0e4d9b7793c16fd98b396ffe6b8db48b8e09f1d2)
quartz: fix crashes that sometimes happened on the first key press

because nobody has called gdk_keymap_get_for_display() before.
Now we simply make sure the default display's keymap exists
if somebody calls any gdk_keymap_*() function with a NULL
keymap (which is an allowed value).
build: fix --disable-man

The third argument to AC_ARG_ENABLE is the action done when
the argument is specified, not when it is enabled.
This resulted in --disable-man enabling those.

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>
Merge branch 'gtk-2-24' of git://git.gnome.org/gtk+ into gtk-2-24