unique_ptr and rework UUID generation

[black-sliver]

• use unique_ptr for auto-created data storage and websocket
• fix AP_NO_DEFAULT_DATA_PACKAGE_STORE code path not working
• rework UUID generation
  • use fstream instead of FILE*, hopefully getting rid of MSVC warnings
  • when a UUID (cache) filename is supplied, this now generates 256 different UUIDs based on a new optional "hostname" parameter. This can be used to send different string to different rooms/hosts and, if used, should be the url (host:port) without ws:// or wss://
  • if no filename is supplied, this generates a random one every time, which is currently completely fine (until we reuse it for competitive or the like)
  • the updated cache file should be forwards and backwards compatible
• Deprecate get_location_name without game