Support 'this week' as a date specifier

go/remind/remind.go

	"fmt"
	"os"
	"sort"
	"strings"
	"time"
)
			case "today":
				min = truncateHours(time.Now())
				max = min.Add(24 * time.Hour)
			case "this":
				if flag.NArg() > start+1 && flag.Arg(start+1) == "week" {
					min = truncateHours(time.Now())
					min = min.AddDate(0, 0, -int(min.Weekday()))
					max = min.AddDate(0, 0, 7)
				} else {
					fmt.Fprintf(os.Stderr, "invalid specifier: '%s'\n", strings.Join(flag.Args()[start:], " "))
					os.Exit(1)
				}
			default:
				fmt.Fprintf(os.Stderr, "unknown command '%s'\n", cmd)
				os.Exit(1)