reload
Atomically reloads the registry by:
Resetting the registry to an empty state, i.e. clearing all entries and tags.
Applying configure to the registry.
Freezing the registry.
Entries that existed before the reload but are not re-registered are created through the unknown-entry factory. The reload fails if no such factory is configured. Previously registered tags that are not re-registered are retained with empty contents.
Throws
If the registry is not reloadable.
If this method is called before an entry or tag referenced in an entry or entry set is registered.