Add ability to delete maps

[huderlem]

This one might be a bit tricky because there are many places in the decompilation projects that would be affected. And what if another map has a warp that points to the deleted map? Lots of things to consider.

[RevoSucks]

from the Discord:

in a better map editor there might be an option to "Delete Anyway"
but default is no
that way someone can do quick work of a bunch of maps by deleting anyway
so they dont need to hand delete a bunch for each
like if someone is redoing a region
they want the whole region deleted
it would be really slow to do one at a time
so i think a "Delete anyway" option would work, but it should be not easy to misclick
and a confirmation Yes/No after
with no default highlighted, of course