Request: SetChecked and SetIndex funcs about ui

[andlabs]

Checkbox.SetChecked() added; will add the Combobox/Listbox ones soon.

[krolaw]

Looking forward to it. Thanks.

[andlabs]

Rewrite notes:

• SetChecked() implemented
• I'm not going to add Combobox/Listbox initially, instead jumping first to Table when I can (to implement the more complex yet more useful controls first); Table will have a SelectIndices() function, h owever, and so will Combobox/Listbox when I add them back

[andlabs]

Table done

[andlabs]

Going to close this issue for now.

I still don't plan on adding Checkbox and Listbox right now; I did drop them into the Future Plans file (future in the main directory) along with a reminder to write a Select() function, which will truly fix this bug. (Checkbox.SetChecked() is there already.)

Thanks in the meantime!