Proposed BaseAnnotationTool updates

[rjackey]

o +wt+tool+BaseAnnotationTool.m - I made significant updates to isClickableAxes() to resolve cases where the mouse pointer did not properly detect whether it was over a valid axes or not; in onMousePress_private() and onMouseRelease_private() and onMouseMotion_private() I use either obj.ClickableAxes.CurrentPoint when e.intersectionPoint is all nans (happens near the edge of the axes, outside the clipping area);

[rjackey]

@altmany I have merged in the changes that appear to be generic. I think it would be useful to have a way to insert a custom filter for mouse actions. That may help in customer-specific use cases where we want to ignore the mouse actions based on the hit part of the drawing. Maybe additional properties of type function_handle that must return a true/false, then if populated the callbacks would exit early?

If you'd like to go ahead with that change, I would prefer if you can propose what's needed here and send me code or submit updates directly.

[rjackey]

I had to back out some changes due to issues.

For example, it allowed me to place vertices outside of the image stack. I assume that is not intended?