Added support for a preliminary Preferences Dialog

Dirk asked me to try to make it more modern, so I
used as a base, the Firefox preferences. currently
it saves / loads the preferences, and also smits
a signal 'preferencesChanged' that should be connected
to anything that uses preferenes, via the PreferencesDialog::intance()
object. In the future, I plan to make it have a signal / slot for each
member that changes.

I also moved the icons to a new folder this time, because the
amount of icons is now more than just two, and it was
becoming messy.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>

qt-ui/preferences.h

@@ -0,0 +1,26 @@
+#ifndef PREFERENCES_DIALOG_H
+#define PREFERENCES_DIALOG_H
+
+#include <QDialog>
+
+namespace Ui{
+	class PreferencesDialog;
+}
+
+class PreferencesDialog :public QDialog{
+Q_OBJECT
+public:
+	static PreferencesDialog* instance();
+
+signals:
+	void settingsChanged();
+
+public slots:
+	void syncSettings();
+	
+private:
+	explicit PreferencesDialog(QWidget* parent = 0, Qt::WindowFlags f = 0);
+    Ui::PreferencesDialog* ui;
+};
+
+#endif