kernel: fix segfault on Windows when program closed
kernel: fix segfault on Windows when program closed

Don't force destruction of all registered instances.
Probably Python deletes some of them and later we try to delete them
again, causing crash.
It's not really a good decision, but now it is acceptable.

uentity/bluesky,uentity/bluesky,uentity/bluesky,uentity/bluesky,uentity/bluesky