Revision 1219

Update to the layer interface: Direct access to the table,
shapetable, shapefile and filename attributes is now actively
deprecated by issuing deprecation warnings for all places where
this happens.

* Thuban/Model/layer.py (Layer.__getattr__): New. Implement access
to the instance variables table, shapetable, shapefile and
filename via __getattr__ so that we can issue a deprecation
warning.
(Layer.SetShapeStore): Don't set the deprecated instance variables
any more
(Layer.SetShapeStore): Don't use deprecated layer instance
variables
(Layer.Destroy): No need to explicitly remove the instance
variables any more
(Layer.GetFieldType, Layer.Shape): Don't use deprecated layer
instance variables

* Thuban/UI/classgen.py (ClassGenDialog.__init__)
(GenUniformPanel._OnRetrieve, GenUniquePanel._OnRetrieve)
(GenQuantilesPanel.GetList, GenQuantilesPanel.OnRetrieve): Don't
use deprecated layer instance variables

* Thuban/UI/classifier.py (Classifier.__init__): Don't use
deprecated layer instance variables

* Thuban/UI/identifyview.py (IdentifyListCtrl.selected_shape)
(IdentifyGridCtrl.selected_shape): Don't set the deprecated layer
instance variables

* Thuban/UI/tableview.py (LayerTableGrid.select_shapes): Don't use
deprecated layer instance variables

* Thuban/UI/mainwindow.py (MainWindow.LayerShowTable): Don't use
deprecated layer instance variables

* Thuban/Model/save.py (SessionSaver.write_layer): Don't use
deprecated layer instance variables

* Thuban/UI/renderer.py (MapRenderer.draw_shape_layer)
(MapRenderer.polygon_render_param): Don't use deprecated layer instance
variables

* test/runtests.py (main): Turn Thuban's deprecation warnings into
errors so that they're cought by the tests

* test/test_load.py (TestSingleLayer.test): Don't use deprecated
layer instance variables