[oslc-core] OSLC Core spec nits

[Jim des Rivieres]

Small small nits in the ServiceProviderCatalog spec in 
http://open-services.net/bin/view/Main/OSLCCoreSpecDRAFT

> oslc:serviceProvider (Resource of type oslc:ServiceProvider, one-or-many
): describes a service offered by the service provider. 

Should be zero-or-many, to allow catalogs with nothing but sub-catalogs.

> oslc:serviceProviderCatalog (Resource of type 
oslc:ServiceProviderCatalog, one-or-many): describes a service offered by 
the service provider. 

Should be zero-or-many, to allow catalogs that do not have sub-catalogs.

---jim