Added the Temperature Graph with its related classes. A Temperature Axis
is also created so the item is plotted on the right place.
Currently the Temperature Axis is just like the depth axis - top is
zero, wich means that the graph is inverted.
Also, the Temperature axis is being displayed as this helps debugging.
Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>