Add user-managed deletion policy (soft-delete)

[gberche-orange]

Expected behavior

As a marketplace user

• In order recover from a service instance deleted my mistake
• I need to self manage the deletion policy of my service instance, including
  • request some hard delete (e.g. for transient instance created in pipelines or smoke tests)
  • undelete a service instance

Sample UX

# create a service instance with soft delete enabled by default
cf create-service p-mysql 10mb my-db  

# request a delete (resulting in soft-delete)
cf delete-service my-db -f

# request recovery of a deleted service instance
cf create-service p-mysql 10mb my-db  -c '{"recover-soft-delete":true}'

# Disable soft delete on a transient instance (e.g. smoke test)
cf create-service p-mysql 10mb my-db  -c '{"hard-delete":true}'

# request a delete (resulting in hard delete)
cf delete-service my-db -f

# Update deletion policy on an existing instance to 10 days
cf create-service p-mysql 10mb my-db  -c '{"hard-delete":false, "retention-duration":"10d"}'

# Display currently configured deletion policy
cf service p-mysql 

As an osb-cmdb operator

• in order to track service instances numbers
• I need soft-deleted instances to be available in the cmdb-inventory

Observed behavior

COA manages soft-deletes, see https://github.com/orange-cloudfoundry/paas-templates/issues/872

Affected release

Reproduced on version x.y -->