statistics: add a skeleton StatsManager class

In analogy to "QMLManager", add a "StatsManager" class,
which manages the statistics module on mobile.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

mobile-widgets/statsmanager.h

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifndef STATSMANAGER_H
+#define STATSMANAGER_H
+
+#include "stats/statsview.h"
+#include "stats/statsstate.h"
+
+class StatsManager : public QObject {
+	Q_OBJECT
+public:
+	StatsManager();
+	~StatsManager();
+	Q_INVOKABLE void init(StatsView *v);
+	Q_INVOKABLE void doit();
+private:
+	StatsView *view;
+	StatsState state;
+};
+
+#endif