timelinepoints: implemented saving/loading into project files

app/project/item/sequence/sequence.cpp

@@ -97,6 +97,10 @@ void Sequence::Load(QXmlStreamReader *reader, XMLNodeData& xml_node_data, const
       }
 
       set_audio_params(AudioParams(rate, layout));
+    } else if (reader->name() == QStringLiteral("points")) {
+
+      TimelinePoints::Load(reader);
+
     } else if (reader->name() == QStringLiteral("node") || reader->name() == QStringLiteral("viewer")) {
       Node* node;
 
@@ -150,6 +154,9 @@ void Sequence::Save(QXmlStreamWriter *writer) const
 
   writer->writeEndElement(); // audio
 
+  // Write TimelinePoints
+  TimelinePoints::Save(writer);
+
   foreach (Node* node, nodes()) {
     if (node != viewer_output_) {
       node->Save(writer);