Fixed update in rackspace, it now also uses the prefixed location.
Fixed update in rackspace, it now also uses the prefixed location.

sachintaware/flysystem,mhlavac/flysystem,twistor/flysystem,nao-pon/flysystem,sohelrana820/flysystem,oswaldderiemaecker/flysystem,dshafik/flysystem,CarsonF/flysystem,barryvdh/flysystem,mhlavac/flysystem,rossriley/flysystem,Amrit01/flysystem,concrete5/flysystem,mapyo/flysystem,hannesvdvreken/flysystem,dstockto/flysystem,farmisen/flysystem,twistor/flysystem