Change strategy for handling true and false to avoid some initialization order problems and improve performance. Add support for negative integer literals. Update samples to reflect true/false change.

#{
	main <- {
		foo <- :n {
			if: n < 10 {
				true
			} else: {
				foo <- :n { n }
			}
			foo: n + 1
		}
		print: (string: (foo: 0))
	}
}