Pref for visibility of navigation arrows in paged display

[JayPanoz]

At the moment navigation arrows are displayed in paged display as a default, with the following behaviour:

• they are displayed on load and when switching from scrollable to paged
• tapping/clicking at the center of the screen dismisses them (but don’t reenable them)
• they are displayed on hover
• they are displayed on top of the content on smaller breakpoints
• they are displayed on each side of the publication’s content’s container on larger breakpoints

You can also set their size and offset from the edges of the main container/screen.

A preference should be created in order to set the visibility of these arrows, and let people disable them entirely if they don’t want to use them.