Fixes for many issues in flowview, graphing window, and frame playback.

In FlowView:
- Drastically improved functionality of live mode. It actually works now
- Fixed several crash bugs
- Program didn't used to pick up new frames properly. This is now corrected.

In Graphing window:
- Fixed dynamic updates to work properly even under heavy bus loads

In frame playback:
- Fixed a bug where single stepping through frames didn't send them over canbus

deltamodel.h

@@ -0,0 +1,25 @@
+#ifndef DELTAMODEL_H
+#define DELTAMODEL_H
+
+#include <QAbstractTableModel>
+
+class DeltaModel : public QAbstractTableModel
+{
+    Q_OBJECT
+
+public:
+    explicit DeltaModel(QObject *parent = 0);
+
+    // Header:
+    QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override;
+
+    // Basic functionality:
+    int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+    int columnCount(const QModelIndex &parent = QModelIndex()) const override;
+
+    QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
+
+private:
+};
+
+#endif // DELTAMODEL_H