Updates to region map for Porymap

[GriffinRichards]

These are both breaking changes for Porymap, do not merge until a new version is released that supports this.

• Move the region map layout from a .bin file to C. Now that the layout uses constants it will update automatically if the value of any MAPSEC changes. This would happen repeatedly for anyone inserting new map sections while keeping MAPSEC_NONE conveniently last in the list.
• Move the region map graphics that Porymap reads into the region_map folder with the rest of the graphics.