Tags for isometric and top down, and implement in all packs

Most users will either want top-down or isometric icons on a given map, but there’s currently no way to filter to those stamps consistently. There is an “Isometric Icons” tag, but it appears to only be in use in the Fantasy World pack, and not in any of the other packs. It would be useful to have a general ‘isometric’ and ‘top down’ tag, and implement it throughout packs so users can quickly filter to the type of icons they need.