Fix axis labeling modes
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
Currently vtkAxis has 3 "behavior" modes:
CUSTOM was added to support explicit labeling in ParaView, but that's not working correctly.
A cleaner solution (as discussed) is as follows:
1> vtkAxis' "behavior" mode will only control how the axis determines its range i.e. AUTO == based on data, and FIXED == using user-specified min/max. (No CUSTOM anymore).
2> vtkAxis will have labeling mode flag that controls how labels are placed (independent of how the axis ranges are decided). This can simply be a boolean (or enum) that indicates if the labels are placed automatically or only at user-specified values. If set to use user-specified values, then the "TickLabels" are used and labels are placed at only those values. Not that as user-zooms, the axis ranges change by the labels are still shown at only the indicated locations (similar to what would was expected in pase with CUSTOM behavior).