Group
		container.go: add Group to the list of controls in the description of container
	Mac OS X: NSBox
		container_darwin.m: figure out if our setFrameSize: thing applies to resizing the groupbox as well
Control
	Enable()
	Disable()
Table
	more column types: "// As such, a Table renders a []struct{...} where each field of the struct can be a string, a number, an image, or a checkbox."
		table_darwin.m: constructor
		table_unix.c: goTableModel_get_column_type(), goTableModel_get_value()
	multiple selection

so I don't forget, some TODOs:
windows
	- backgrounds are not transparent
mac os x
	- applicationShouldTerminate: not handled