That’s a great trick, thank you for sharing the tutorial.
As to your question – which plugin do you mean? I can see the Screw modifier in my version (2.78.5) but it is possible that it came with a plugin I have enabled. Or do you mean the part where he uses vertices to create the profile of the bottle? He is adding Single Vertex, but you can achieve the same thing if you add a plane (or any primitive mesh), go to Edit mode, select everything with A and delete vertices. You will still keep the “container”, it just won’t have any vertices in it. Then, still in Edit mode, you can Ctrl + click to insert a vertex. Whether it is left or right mouse button depends on your user preferences. I select geometry with the left button, so to insert vertices I need to use the right button.
