code: public Observable<Page<CertificateItem>> getCertificatesAsync(final String vaultBaseUrl, final Integer maxresults, final Boolean includePending) {
          return getCertificatesWithServiceResponseAsync(vaultBaseUrl, maxresults, includePending)
              .map(new Func1<ServiceResponse<Page<CertificateItem>>, Page<CertificateItem>>() {
                  @Override
                  public Page<CertificateItem> call(ServiceResponse<Page<CertificateItem>> response) {
                      return response.body();
                  }
              });
      }
docs: List certificates in a specified key vault.
  The GetCertificates operation returns the set of certificates resources in the specified key vault. This operation requires the certificates/list permission.
  
  @param vaultBaseUrl The vault name, for example https://myvault.vault.azure.net.
  @param maxresults Maximum number of results to return in a page. If not specified the service will return up to 25 results.
  @param includePending Specifies whether to include certificates which are not completely provisioned.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the observable to the PagedList&lt;CertificateItem&gt; object