Automatically parse dates in Safari for adding to calendar
If you have a force touch trackpad (built in or magic trackpad) you can force touch on dates, and then you'll be able to add them to your calendar.

If you don't have a force touch trackpad, but a normal trackpad, you can just move the cursor on top of a date, and the touch the trackpad with three fingers, and then you'll be able to add them to your calendar.