Introduce Settingsprovider to read settings

Previously, it was in the configprovider.cpp.

Now, it has been split to this file

settingsprovider.h

@@ -0,0 +1,18 @@
+#ifndef SETTINGSPROVIDER_H
+#define SETTINGSPROVIDER_H
+
+#include <stdexcept>
+#include <QSettings>
+
+class SettingsProvider
+{
+private:
+	QSettings *settings;
+public:
+	SettingsProvider(QSettings &settings);
+	virtual QStringList userEntriesPaths() const;
+	virtual QStringList systemApplicationsEntriesPaths() const;
+	virtual bool singleInstanceMode() const;
+};
+
+#endif // SETTINGSPROVIDER_H