Layouts (#189)

* Layout WIP

* Widgets/BoxLayout: Fix layout algorithm

* Widgets/BoxLayout: Fix box layout algorithm for good

* SDK/Widgets: Remove padding

* Sdk/Widgets: Make use of minimum/preferred size

* Sdk/TextAreaWidget: Add Minimum/PreferredSize to TextArea

* Sdk/Widgets: Add height/width variants of get/set fixed, maximum, minimum and preferred size methods

* Sdk/BoxLayout: Remove useless code

* Sdk/TextAreaWidget: Fix compilation

* Widgets/TextAreaWidget: Fix cursor position

SDK/include/NDK/Widgets/BoxLayout.inl

@@ -0,0 +1,15 @@
+// Copyright (C) 2017 Jérôme Leclercq
+// This file is part of the "Nazara Development Kit"
+// For conditions of distribution and use, see copyright notice in Prerequisites.hpp
+
+#include <NDK/Widgets/BoxLayout.hpp>
+
+namespace Ndk
+{
+	BoxLayout::BoxLayout(BaseWidget* parent, BoxLayoutOrientation orientation) :
+	BaseWidget(parent),
+	m_orientation(orientation),
+	m_spacing(5.f)
+	{
+	}
+}