gtk: Prepare for GTK+ 3.0 by not using members directly

GTK+ 3.0 enabled G_SEAL which means direct member access is
not possible anymore. This means we should use the getters
and setters provided by GTK. The good thing is that we can
remove some of our custom getters/setters. In the case of
GtkAllocation the API works differently to what we had so
we need to add a compat call.
GtkPlacer is only used with Blox and I didn't attempt to
run the GTK+ version of it.

2014-05-26  Holger Hans Peter Freyther  <holger@freyther.de>

	* MoreFuncs.st: Remove GtkWidget>>#setFlags:,
	GtkWidget>>#unsetFlags:, GtkWidget>>#getFlags,
	GtkScrolledWindow>>#getHscrollbarVisible and
	GtkScrolledWindow>>#getVscrollbarVisible. Change the
	return type to double in GtkAdjustment>>#getUpper,
	GtkAdjustment>>#getLower and GtkAdjustment>>#getPageSize.
	Change GtkWidget>>#getAllocation to use >>#getAllocation:
	on GCed memory.
	* example_entry.st: Use the new setters in Gtk.
	* gst-gtk.c: Remove gstGtkGetFlags, gstGtkSetFlags,
	gstGtkUnsetFlags. gstGtkWidgetGetAllocation.
	Map gstGtkGetState, gstGtkGetWindow, gstGtkAdjustmentGetLower,
	gstGtkAdjustmentGetUpper, gstGtkAdjustmentGetPageSize,
	gstGtkDialogGetVBox and gstGtkDialogGetActionArea
	directly to GTK+.
	* placer.c: Modernize the GTK+ api usage
kernel: Fix return of RecursionLock>>#critical:

In case the lock is not locked by the current process yet
>>#critical: will not return value of the block. This is
different to how Semaphore>>#critical: works. Fix it and
add a testcase for both cases.

2014-06-21  Holger Hans Peter Freyther  <holger@freyther.de>

	* kernel/RecursionLock.st: Return the result of >>#critical:

2014-06-21  Holger Hans Peter Freyther  <holger@freyther.de>

	* kernel/RecursionLockTests.st: Add test for RecursionLock