Adding shading rules from b/19425382
Adding shading rules from b/19425382

agibsonccc/cloud-bigtable-client,googleapis/java-bigtable-hbase,dmmcerlean/cloud-bigtable-client,rameshdharan/cloud-bigtable-client,waprin/cloud-bigtable-client,kevinsi4508/cloud-bigtable-client,googleapis/java-bigtable-hbase,kevinsi4508/cloud-bigtable-client,sduskis/cloud-bigtable-client,sduskis/cloud-bigtable-client,googleapis/java-bigtable-hbase,derjust/cloud-bigtable-client,rameshdharan/cloud-bigtable-client,ceocoder/cloud-bigtable-client