[1.0.0] Resolve the namingContexts from storage. Correct SIGHUP.

[ChadSikorra]

Two fixes here:

• The namingContexts advertised from the RootDSE / enforced by the backend should come from actual storage. Not the options. This is a holdover from when the server was literally a shell with no storage backend. This has significantly changed.
• Writing a namingContext requires a system level operation. So it would need to be done in seed or applyChanges. It might make sense to have a writable config populated by the system or something. But currently not planning to go that route.
• The SIGHUP should be an unimplemented to do. Just want to suppress the builtin behavior where a SIGHUP triggers a server shutdown, which it should not do.