This adds the Dubious Disc Salesman to Cinnabar Pokemon Centre. I chose this area because it's late in the game and it seemed a bit iffy to constantly have to go with Pokemon Centres not in towns. Cinnabar has some connection to Silph, so it makes more sense than just balancing.
There are probably improvements that could be made (eg. a quote as you buy) but the salesman code is surprisingly brittle so I'd rather not break stuff for hours for something that already works perfectly fine.
* Update sign to bg_event #289
* Rename warp to warp_event
* Replace object to object_event
* Move warp macro parameter from warp x, y, id, map to warp_event x, y, map, id