Property :: canCreate - Can instance(s) be created for collection

The function checks, whether new instances can be created for the collection or not. The function returns true, when creating a new instance and adding it to the collection is possible. Otherwise, the function returns false.

Returning true always implies canUpdateCollection(), but not necessarily the reverse. There are several reasons rejecting creating an instance:

1. The property handle is opened for read, only
2. The collection is not an owning collection and not extent based
3. Instance cannot be created into base extent (super set.canCreate())
4. Inverse reference exists but cannot be updated (inverse.canUpdateCollection())
5. Maximum number of instances in the collection exceeded
6. The current application does not have rights for inserting the instance (disabled by context)
7. The property handle is invalid.
8. Updating is denied by context handler (client or server) TypeContext::canCreate()