Updates to game mechanics

Added new sounds and ambience.

Added a way to transition between scenes in a lore accurate way.

Currently there are 4 different levels which are randomly generated, I will be putting together a logic tree of how these work and which maps have entrances / exits to other maps. This will then become an artefact that the player can collect and view to help them navigate.

Next steps:

- create more events for level 0 to make up for the fact there are few entities.

- add to ambience and find a way of creating a crt effect using hdrp.

- add a pitfalls event, a tall structure event and a claustrophobia event.

- start development on level 1.