napi add env cleanup hook

NODE_EXTERN napi_status napi_add_env_cleanup_hook(napi_env env,
                                                  void (*fun)(void* arg),
                                                  void* arg);

Registers fun as a function to be run with the arg parameter once the current Node.js environment exits.

A function can safely be specified multiple times with different arg values. In that case, it will be called multiple times as well. Providing the same fun and arg values multiple times is not allowed and will lead the process to abort.

The hooks will be called in reverse order, i.e. the most recently added one will be called first.

Removing this hook can be done by using [napi_remove_env_cleanup_hook][]. Typically, that happens when the resource for which this hook was added is being torn down anyway.

For asynchronous cleanup, [napi_add_async_cleanup_hook][] is available.