Include cluster delete capabilities to oebs-cloud.sh ----------------------------------------------------
Include cluster delete capabilities to oebs-cloud.sh
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1. Why is this change necessary?

- Currently, those using the oebs-cloud.sh script to create kubernetes clusters on AWS
  perform a manual delete (via terraform destroy) to bring down their infra. Performing such
  an operation would still leave residual S3 buckets w/ stale cluster objects in them. Also,
  the terraform template files and the autogenerated config scripts need to be cleaned up
  manually.

2. How does this change address the issue?

- This commit performs an ordered delete by first performing a cluster delete via kops
  (which deletes the cluster components and also clears the cluster state in the S3 bucket
  rendering it empty), followed by delete of the s3 bucket via awc-cli & clean-up of the
  terraform templates and config files. These operations are performed after user confirmation.

3. What side effects does this change have?

- None

yudaykiran/openebs