Fix API to be backwards compatible
Fix API to be backwards compatible

harlowja/pymemcache,pinterest/pymemcache,adamchainz/pymemcache,sontek/pymemcache,ewdurbin/pymemcache,bwalks/pymemcache,mbrukman/pymemcache,dive-tv/pyelasticache_client,pinterest/pymemcache,sontek/pymemcache,thedrow/pymemcache