[Cdk-jchempaint] delete bond behaviour

[Ralf S. <ra...@ar...>]

Hello,
I'm looking for feedback on a use case where I'm not sure
what users would expect. As that case results at the moment
in an exception I offer you the choice to decide how I'll fix it.

                  H3C---CH3

Assume you have ethane on the canvas. Now you click Select
Rectangle and draw a selection rectangle around the first C,
the bond middle not included, so your selection *is practically
the first C. Deletion will leave CH4, and I hope you agree.

Now draw the rectangle a bit wider such that the bond middle
is included, selecting C *and bond. 1. What will remain when you
delete both? CH4 or nothing? 2. Would you expect deleting the bond
only to leave two methanes or nothing?

Regards,
Ralf Stephan