JcrPackageManagerImpl#extract() javadoc mentions not existent "register" property

According to the API for the JcrPackageManagerImpl#extract method, it seems there should be a way to avoid storing the package when extracting a package.
Currently, a package without content is always stored.

The API mentions the registerPackage flag to avoid storing package, but it seems the implementation is missing.

Not storing a package at all is desirable for Sling Content Distribution.

cc tripod

[0] https://github.com/apache/jackrabbit-filevault/blob/trunk/vault-core/src/main/java/org/apache/jackrabbit/vault/packaging/JcrPackageManager.java#L226-L252