Deprecates store.loadQueryResults used for remote queries so that we can just use store.dataSourceDidFetchQuery for both local and remote queries.  All the loadQueryResults method did was set the store keys on the record array and called dataSourceDidFetchQuery anyway.  But having this extra function with a much different name is confusing for developers and requires checking if a query is local or remote before calling the matching method.  Instead, we can just call the one method dataSourceDidFetchQuery for queries and optionally pass in the storeKeys for a remote query.

Also added better documentation for using dataSourceDidFetchQuery.