Add method to retrieve the 'directory features' for the directory a new user will be created in

Based on jwalton's recommendation on EMBCWD-972, CrowdService could be extended with a new method allowing the products to query what will be the 'directory features' for the directory a new user will be created in.

This was suggested as an alternative to adding a method allowing User to be created within a specific directory.

This issue replaces EMBCWD-978 since the required changes impact more than the Embedded Crowd component.