Settings

I have updated the Tool and Engine classes to now have virtual functions
to handle saving settings. Any subclass (plugin) that uses this should
call the base class functions too. For Tool the base class doesn’t
actually do anything but in the future we may do something with it. For
Engine it actually saves the description and name so that you don’t have
to. It is possible that when we get our native format going, the
engines may have to save their own molecule information but maybe not.
We’ll cross that road when we get there.

Anyways, the reason I’m sending this email is to ask for people to
gradually add the (read|write)Settings functions to tools and engines.
I already did LabelEngine and DrawTool. Just pick one a day or
something.


Donald