- BeanShell seems not to import the second time a BeanShell interpreter is
  opened (reported by Stephan Saalfeld).

- Enable to set breakpoints via the Breakpoints menu and F9 (IIRC).

- if there are images on which the plugin wants to work, they have to be
  transported to the other virtual machine.  Mark them with the "(Debugging)"
  suffix, like the main window.

- when debugging finished, give the user a chance to save resulting images
  or some such before closing the debuggee.

- Integrate Fiji Build much better.

- Identify non-explicit imports and add an option to make them explicit.
