Save M3L into ROM

[mchlnix]

To save a level into the ROM it needs to have an object and an enemy offset. So there needs to be some way to input those before saving.

Maybe some check for the available space would work.

Or should the world and level numbers, that are in the m3l file be used instead?

[mchlnix]

Since the object set might change and it is encoded into the same byte the row of the square of the level is, it is a bit more complicated. Just letting the user type in offsets is also kinda bad, though.

So this might have to wait until we just parse the whole rom for levels, instead of reading them from a file.

[mchlnix]

implemented