Add option to include evicted entries in snapshots

[leighmcculloch]

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The snapshot command uses history archives to build a snapshot of relevant ledger entries for testing. Because it only uses history archives of a specific ledger it is unable to include evicted entries that otherwise might be restorable at that ledger.

It would be helpful for testing if the command could include evicted entries as well.

Discussion: https://discord.com/channels/897514728459468821/966788672164855829/1402729874119987393