Add a List to the GUI.
Prototype of a GUI for manual classification using overlays.

Initial version is a copy of sandbox/swing_gui.py
Proof-of-concept for using inline Java Weaver code.
Protoype for converting Netbeans code to Python.
Add imports, main frame and some aliases.
Check if ROIs are defined, exit otherwise.
Less verbosity on Weaver stuff.
Update description about non-interactive mode.