Test all of the Cell API for Linear, Quadratic and BiQuadratic cells
(except for clipping and contouring). Attempt to numerically validate
tested methods.

This Unit Test has uncovered the following errors and/or
inconsistencies:

DOC: Cells that use Newton's method to find coordinates did not
consistently report a bad determinant. All cells now use
vtkDebugMacro.

BUG: Polygon
Intersection test failed for points on vertices and edges

BUG: Polyhedron
Intersection test failed for points on vertices, edges and faces

BUG: Pyramid
Wrong pcoords for apex.

BUG: QuadraticPyramid
Missing test for apex singularity when finding position

ENH: QuadraticPyramid
Improved shape functions

BUG: QuadraticTriangle
Derivatives() method was changing input pcoords.
EvaluatePosition set pcoord[2] to wrong value.

BUG: BiQuadraticTriangle
EvaluatePosition method set pcoord[2] to wrong value.

DOC: BiQuadraticQuadraticHexahedron
Reported error for divergence of newton's method. Most cells do
not do this

DOC: TriQuadraticHexahedron
Reported error for divergence of newton's method. Most cells do
not do this

BUG: QuadraticPolygon
Derivatives() method was changing input pcoords.

DOC: QuadraticQuad
Copy/paste error describing pcoord transformation
Reported error for divergence of newton's method. Most cells do
not do this