set up deployment account for vsphere when doing automated deploys

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
moved aws automatic deploy specific code into deployment account

Signed-off-by: dmitriy kalinin <dmitriy@pivotallabs.com>
moved cd:deploy code under test
added vphere automated deploy builder
pass in infra/os names to automated deploy
made ArtifactsDownloader#download_release more consistent with #download_stemcell
extract BuildTarget object to know which infra/os/build# automated deploy is running for
renamed automated_deployer to automated_deploy