The Messenger: Add locations to shutting down the generators in Elementals Skyland

[Jouramie]

What is this fixing or adding?

This adds 4 locations in the Elemental Skylands, sent by shutting down the generators. It also adds a Progressive Generator Shutdown item to deactivate each generator one by one. Four of copies of this item should be added to the itempool.

To avoid making the region too linear, the generator doors still open when breaking the lanterns (sending the location), except in the fire island generator room. There, you need all four Progressive Generator Shutdown to unlock the door. So it essentially only gates the Key of Symbiosis location and the right exit behind receiving the items.

The doors in each room also automatically open when receiving enough Progressive Generator Shutdown. This is however only useful on the air island where you can backtrack from the generator shop or the seal checkpoint, if you land a portal rando there.

How was this tested?

I played it in an async with friends, worked great! See also the PR on the mod side, there are a bunch of videos. alwaysintreble/TheMessengerRandomizerModAP#23

If this makes graphical changes, please attach screenshots.

N/A

[Jouramie]

That failing test seems to be a flaky, unrelated to these changes.