Recording stats layout customizable.

Users can select the order, visibility and importance (primary or secondary) of all stats for recording layout from the Settings.
Also, users can select the number of columns per row in the recording layout: 1, 2 or 3.
Finally, show altitude/coordinate from settings have been removed (not needed anymore).
Fixes #659.
Fixes #302.
Fixes #820.

src/main/java/de/dennisguse/opentracks/viewmodels/StatisticsDataModel.java

@@ -0,0 +1,35 @@
+package de.dennisguse.opentracks.viewmodels;
+
+import android.app.Application;
+
+import androidx.annotation.NonNull;
+import androidx.lifecycle.AndroidViewModel;
+import androidx.lifecycle.MutableLiveData;
+
+import java.util.List;
+
+import de.dennisguse.opentracks.content.data.Layout;
+import de.dennisguse.opentracks.services.TrackRecordingService;
+
+public class StatisticsDataModel extends AndroidViewModel {
+
+    private MutableLiveData<List<StatisticData>> statsData;
+
+    public StatisticsDataModel(@NonNull Application application) {
+        super(application);
+    }
+
+    public MutableLiveData<List<StatisticData>> getStatsData() {
+        if (statsData == null) {
+            statsData = new MutableLiveData<>();
+        }
+        return statsData;
+    }
+
+    public void update(TrackRecordingService.RecordingData recordingData, Layout layout, boolean metricUnit) {
+        new Thread(() -> {
+            List<StatisticData> statisticDataList = StatisticDataBuilder.fromRecordingData(getApplication(), recordingData, layout, metricUnit);
+            statsData.postValue(statisticDataList);
+        }).start();
+    }
+}