Release of Daml SDK 0.13.54

Sandbox

• Removed the warnings regarding static time and scenarios on
  initialization. We will not deprecate these until we have a stable
  alternative.
• If no ledger ID is provided when running against an existing ledger,
  use the existing ID. Previously, Sandbox would fail to start.

Daml Standard Library

• Add subtractDays to the Daml Standard Library.