Making custom map names show up on the world map

[Regaccio]

Currently, giving buildings custom names doesn't actually make their name show up on the overworld map, and in some other instances like leaving the map. This makes it so that when you rename something the new name shows up all the time. e.g. naming a shop Snail-Mart and walking over it will show "You see Snail-Mart." instead of "You see Shop."

adata(ADATA_FESTIVAL, gdata(GDATA_AREA)) = 0 is commented out in map_user.hsp because that causes unwanted behavior when canceling from the rename screen, and has no purpose otherwise. ADATA_FESTIVAL was already set to 9999 whenever the player gave a map a custom name, in this code that's being used to detect if a map was custom-named, basically.

There's also a small fix(?) where the "You named it [name]" is put after the screen_refreshFull so the player actually sees it, and a botched copypasta probably from the creature renaming code was fixed to show the new map name.

[Ruin0x11]

What about the case when the player wants to remove the custom name of the current map? I think that could be the purpose of this code.

[Regaccio]

In the unmodified game, entering nothing in the prompt doesn't reset the name to default. I think that might be nice functionality to have, but if that's supposed to be the purpose of this code, it doesn't work. In any event, the player can just enter "Shop", "Crop", etc. and achieve the same thing so I didn't think it was important to add.