Top and bottom padding for file and folder names

[pornelus]

To improve the readability of file lists, it would be great to have some basic option to control the height of of a row with padding. At least for me, a bit of space between rows makes the readability greatly improved.

[mikekazakov]

This layout information is a table, not a single value, e.g.:

nimble-commander/Source/NimbleCommander/NimbleCommander/States/FilePanels/Brief/PanelBriefView.mm

Line 32 in 1a11ddf

static constinit const std::array<LayoutDataT, 21> g_FixedLayoutData = {{

Right now it's hardcoded, but in theory can be moved into a json-based config if done carefully.
I'd be ok with such change, but it needs to be implemented, so if anybody is interested enough - PRs are welcome.

[tiagof]

An attempt at this #551.
Still incomplete as I've exhausted my knowledge of "mac ui development". (see the PR for details)

Would love to have this feature. If anyone can pick it up and finish the PR....

[tiagof]

PR was merged. Row height (padding) can now be configured in the Theme.