Feature request: change subsector list into a grid

[IvanSanchez]

In the "sector" view, the list of subsectors is currently literally a list:

It would be nicer to have that formatted as a 4x4 grid, e.g.:

A:  Menorial   |   B: Egyrn       |   C: Pax Rulin   |   D: Gazulin
E: Yggdrasil   |   F: Dpres       |   G: Sindal      |   H: Tobia
I: Nora'a      |   J: Goertel     |   K: Tlaiowaha   |   L: The Borderland
M: Ranib       |   N: Silraaihe   |   O: Hkea'as     |   P: Binary

...as that way is more spatially similar to the actual disposition of the subsectors.