It's a small popup trailer behind an F150. You definitely do not need to add weight distribution (spring bars) to the hitch.
As far as a sway bar. If you load the Aliner properly with the majority of the added weight at or in front of the axle then probably not.
If you get too much wiggle when towing, or you have to put too much weight behind the axle the yes I would get a standard inexpensive sway bar. Barney posted a picture of one above called a Friction Sway Control. But I would just tow it first and see how it performs before adding anything to it.