Revision 1551

* Thuban/Model/data.py (ShapefileStore.Shape): For consistency, a
Shape object will always have the coordinates as a list of list of
coordinate pairs (tuples).
(Shape.compute_bbox): Adapt to new representation.

* Thuban/UI/viewport.py (ViewPort.find_shape_at)
(ViewPort.LabelShapeAt): Adapt to new coordinate representation in
Shape objects.

* test/test_shapefilestore.py
(ShapefileStoreTests.assertFloatTuplesEqual)
(ShapefileStoreTests.assertPointListEquals): Rename to
assertPointListEquals and change purpose to checking equality of
the lists returned by Shape.Points().
(TestShapefileStoreArc.test_shape)
(TestShapefileStorePolygon.test_shape)
(TestShapefileStorePoint.test_shape): Use the new
assertPointListEquals instead of assertFloatTuplesEqual

* test/test_layer.py (TestLayer.assertFloatTuplesEqual)
(TestLayer.assertPointListEquals): Rename to assertPointListEquals
and change purpose to checking equality of the lists returned by
Shape.Points().
(TestLayer.test_arc_layer, TestLayer.test_arc_layer)
(TestLayer.test_polygon_layer, TestLayer.test_point_layer)
(TestLayer.test_derived_store): Use the new assertPointListEquals
instead of assertFloatTuplesEqual

* test/test_derivedshapestore.py
(TestDerivedShapeStore.assertFloatTuplesEqual)
(TestDerivedShapeStore.assertPointListEquals): Rename to
assertPointListEquals and change purpose to checking equality of
the lists returned by Shape.Points().
(TestDerivedShapeStore.test_shape): Use the new
assertPointListEquals instead of assertFloatTuplesEqual