Glyph mapper accepts but then ignores per-cell vectors

When using the glyph mapper representation, the orientation and scaling configurations accept cell-data arrays but do not use them (see attached glyph-mapper-cell-normal-fail.zip for data and a state file -- the arrows should not both point the same direction).

Either the arrays should not be listed or they should take effect. The latter is preferred but likely requires a change (e.g., running the "Cell Centers filter internally to generate points where glyphs can be placed).