fix most recent display

the slice syntax doesn't support "slice to x or len()", so we have to
use this idiom. i wonder what one does when wanting to do that and work
with a result, but the answer is either something obvious/idiomatic or
writing a function that does it.

go/feeds.go

			continue
		}
		fmt.Printf("%s: %s - %s\n", fn, f.Title, f.Description)
		fmt.Printf("%s: %d entries\n", fn, len(f.Items))
		for _, item := range f.Items[0:10] {
			fmt.Printf("%s: %s\n", fn, item.Title)
		fmt.Printf("%s: %s - %s (%d entries)\n", fn, f.Title, f.Description, len(f.Items))
		for i, item := range f.Items {
			if i < 10 {
				fmt.Printf("%s: %s\n", fn, item.Title)
			}
		}
	}
}