How to alter touchpad settings on Ubuntu GNOME 16.04?
To be able to set these settings through Terminal or through the gnome-control-center you need to make sure that you have xserver-xorg-input-libinput installed. It appears to be a bug that it is not already installed by default, in order to install simply run:
sudo apt-get install xserver-xorg-input-libinput
After doing so and then logging out and in again you will find new settings in the gnome-control-center's Mouse & Touchpad settings:
You should now also be able to set the touchpad settings through the dconf-editor and gsettings in Terminal.
Related: LP Bug #1586657