Started the code for a grid that knows how to handle itself.

The code for this item is a bit too big to be just the grid
of the dives and I know that, don't bully me. :)
The main idea of this grid is that it knows when it should be
updated. this is a bit different than the old code where all
the painting happened on the same method. This is bad because
it's more code, but it's better because if I break the grid,
only the grid will be broken, and it's easyer to spot the breakage.

in the old code if I did the wrong thing with the graphics context,
the whole graph gots messed out.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-ui/profile/profilewidget2.h

@@ -23,6 +23,7 @@ struct DiveProfileItem;
 struct TimeAxis;
 struct dive;
 struct QStateMachine;
+struct DiveCartesianPlane;
 
 class ProfileWidget2 : public QGraphicsView {
 	Q_OBJECT
@@ -62,6 +63,7 @@ private:
 	DiveRectItem *depthController;
 	DiveRectItem *timeController;
 	DiveProfileItem *diveProfileItem;
+	DiveCartesianPlane *cartesianPlane;
 };
 
 #endif