implemented basic animation curve editor widgets

Frontend is largely done, it just needs backend and connecting to other
widgets to function correctly.

app/window/mainwindow/mainwindow.cpp

@@ -27,6 +27,7 @@
 // Panel objects
 #include "panel/panelmanager.h"
 #include "panel/audiomonitor/audiomonitor.h"
+#include "panel/curve/curve.h"
 #include "panel/node/node.h"
 #include "panel/param/param.h"
 #include "panel/project/project.h"
@@ -137,6 +138,10 @@ void MainWindow::ProjectOpen(Project* p)
   task_man_panel->setFloating(true);
   task_man_panel->setVisible(false);
 
+  CurvePanel* curve_panel = PanelManager::instance()->CreatePanel<CurvePanel>(this);
+  addDockWidget(Qt::BottomDockWidgetArea, curve_panel);
+  task_man_panel->setFloating(true);
+
   connect(node_panel, SIGNAL(SelectionChanged(QList<Node*>)), param_panel, SLOT(SetNodes(QList<Node*>)));
 }