Add a locking mechanism to islands

[Cyclonit]

This PR adds a toggle to lock islands. Locked islands can neither be moved nor have any of their properties changed. This prevents moving islands by accident.

Secondly it serves as a foundation for supporting custom Arctic and Enbesa. Due to the presence of custom triggers and other GameObjects, changing certain islands would break quests in those regions. Locking them does not solve all issues but it is a first step in the right direction.

In the future warning messages should be added if the user attempts to unlock an island containing GameObjects.

[Shad0wlife]

Yeah, this fixes quest triggers that are on the world map but "belong" to an island. BUT we have to make sure that those coordinates don't break when making the map bigger. We might also want to introduce a minimum session size.

[Cyclonit]

Yes, all position updates must either be prevented or be propagated to all relevant objects. I'll look into that later.

[Shad0wlife]

Good idea. Though it might be difficult to identify the relevant objects. Because simple locations might be fine but paths etc get harder. And island rotation would make extra difficult 😅