Rework the settings dialog. Rework all of it. Thoroughly.

Also introduces the ColumnResizer from:
https://github.com/agateau/columnresizer/

gui/ColumnResizer.h

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2011 Aurélien Gâteau <agateau@kde.org>
+ * License: LGPL v2.1 or later (see COPYING)
+ */
+#pragma once
+
+#include <QFormLayout>
+
+#include <QtCore/QObject>
+#include <QtCore/QList>
+
+class QEvent;
+class QGridLayout;
+class QLayout;
+class QWidget;
+
+class ColumnResizerPrivate;
+class ColumnResizer : public QObject
+{
+    Q_OBJECT
+public:
+    ColumnResizer(QObject* parent = 0);
+    ~ColumnResizer();
+
+    void addWidget(QWidget* widget);
+    void addWidgetsFromLayout(QLayout*, int column);
+    void addWidgetsFromGridLayout(QGridLayout*, int column);
+    void addWidgetsFromFormLayout(QFormLayout*, QFormLayout::ItemRole role);
+
+private Q_SLOTS:
+    void updateWidth();
+
+protected:
+    bool eventFilter(QObject*, QEvent* event);
+
+private:
+    ColumnResizerPrivate* const d;
+};