If I use the remote start feature to start my 2015 Jeep Grand Cherokee can I stop it using the remote feature?

I wondered the same thing about my vehicle.  (different make/model than yours)

So - I started it - waited about four or five minutes - and then pushed the button again - and it did turn off.

So - JUST TRY IT.  It will either work or it won't but then you will know.  

Check the owner's manual.

Most remote starts shut off the motor in 10 minutes.

Yes you can. When you turn on your vehicle via remote start, the engine will stay running for a set amount of time. If you do not enter the vehicle in that amount of time, the engine will automatically turn off. This duration can be adjusted. 

It would be foolishly dangerous to design any remote start system which would not allow the owner to change their mind and turn the engine off.

Do what? If you use the remote and then want to stop using it, well if you don't want to use the remote then don't use the remote. Other than that I don't know what you are asking because the question does not make sense.