The io/ioutil package has been deprecated as of Go 1.16, see
https://golang.org/doc/go1.16#ioutil. This commit replaces the existing
io/ioutil functions with their new definitions in io and os packages.
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
The schema is "azureblob".
azureClient provides two ways to set up credential. One approach is to
use an account key stored in env var. This approach is used when
accessing Blob from kops CLI. The second approach is to retrieve
credentials from Instance Metadata Service. This works only when
azureClient is created on a VM that has sufficient privilege to access
a specified blob. This approach is used from nodeup, etcd-manager,
etc.
Ciprian Hacman
justinsb
Eng Zer Jun
Kenji Kaneda