code: public static BaasResult<BaasDocument> fetchSync(String collection,String id){
          return fetchSync(collection,id,false);
      }
docs: Synchronously fetches a document from the server
  
  @param collection the collection to retrieve the document from. Not <code>null</code>
  @param id         the id of the document to retrieve. Not <code>null</code>
  @return the result of the request