Feature request: add an option to set vertical padding

[mroavi]

It would be nice to have the option to set the number of (virtual) blank lines that are displayed above/below the first/last lines of the buffer that is being displayed (this is what I refer to as vertical padding). I noticed that Goyo has this as default:

goyo:

zen-mode:

[miguno]

+1

It would be nice to have support for horizontal padding, too.