User Catalog management

User Catalog management


* Catalog files are dedicated to store feature definition (StartUp)
* A catalog may store any number of StartUps
* Once created a catalog should never be deleted
  - In fact a catalog has a unique ID which is used to identify the
    StartUps it contains. When a catalog is deleted and recreated,
    existing instances of every feature will still reference the old
    catalog ID.
  - instead upgrade it
* Catalog implement the interface CATICatalog
* use this interface to add startups to a caltalog
* DS provides the several method to manage user catalogs, they are
  defined in CATCatalogFactoryServices.h
  - CreateCatalog
  - UpgradeCatalog
  - AccessCatalog
  - SaveCatalog
* To protect the use of your catalog, those methods takes a client ID
* To ensure ascendant data compatibility between subsequent release
  of your application you must follow some rules
  - On StartUp
    . You can add or delete attributes
    . You can change an attribute's initial value
    . You cannot modify an attibute's type or quality
    . You can change its name
  - On a catalog
    . You can add new StartUps, as long as theri names are unique in
     all catalogs.
    . You cannot delte a StartUp or move it to another catalog
    . You cannot change the name of catalog or recreate it