fix day range parsing (zk-org/zk#382) (#384)

internal/cli/filtering.go

@@ -280,7 +280,9 @@ func parseDayRange(date string) (start time.Time, end time.Time, err error) {
 		return
 	}
 
-	start = startOfDay(day)
+    // we add -1 second so that the day range ends at 23:59:59
+    // i.e, the 'new day' begins at 00:00:00
+	start = startOfDay(day).Add(time.Second * -1)
 	end = start.AddDate(0, 0, 1)
 	return start, end, nil
 }