Fix handling of tolerance in vertical direction.

When rastering polygonal data into a stencil, it is necessary to
use tolerances or pixels that lie right on a vertex or edge might
not be counted.  However, the vertical tolerance handling was flawed,
it only worked on convex shapes and could give unacceptable results
on concave shapes.

The new code rasterizes each point twice, once with a positive vertical
tolerance offset and once with a negative vertical offset.  It is slower
than the old code, but will give correct results.

Some baselines were and changed to reflect the additional pixels included
in the stencils now that tolerance is properly applied.

Change-Id: Idc1dc7cbf32476d0bde69dbaef8a287a3e090024
Deprecate the obsolete InsertLine method signature.

The inflection point info is no longer used for anything.

Change-Id: I2db3493f9dcd90acdc6f899f497fcb5402050218
Add test for LassoStencilSource orientations.

This test covers some important code in vtkImageStencilData that
wasn't covered by any previous tests.

Change-Id: I66a63cacab9b41f54db083fce54437a8adda090b
Re-enable vtkPolyDataToImageStencil tolerance.

Thanks to the recent fixes to vtkImageStencilData, the tolerance
can be properly applied during the creation of the stencil.

Change-Id: I5bf5c699eedd8a2cd561b203d5c58070d19da880
Merge topic 'stencil-raster-tolerance' into master

8ef9c888 Re-enable vtkPolyDataToImageStencil tolerance.
c8b25c88 Add test for LassoStencilSource orientations.
257c8b13 Deprecate the obsolete InsertLine method signature.
4a570677 Fix handling of tolerance in vertical direction.