Cardano Updates

WIP. Starting to remove owners from the StakePoolSnapShot

Reward computation is done

Fix and Improve Arbitrary for SnapShot

Move Stake definition to Stake module

Because it conflcicts with our internal type.

Add `DijkstraSpendingOutputFromSameTx` to `DijkstraLedgerPredFailure` to
report when a sub-tx-id is being spent within the same transaction.

Add Dijkstra.Imp.LedgerSpec with tests.

WIP. Starting to remove owners from the StakePoolSnapShot

Reward computation is done

Fix and Improve Arbitrary for SnapShot

Move Stake definition to Stake module

Ensure original `ByteString` can be garbage collected as soon as the hash is computed

`BinaryData` never requests the memoized Hash, so there is no need to
retain the `ByteString`, it is better to use the already available
`ShortByteString`

Upon decoding of a type it is quite possible to have a much larger
lazy `ByteString` that is being supplied to the decoder, eg. decodign Tx
in a Block.

In order to ensure that that lazy buffer is not retained in memory we
need to make a full copy of the slice, but only during decoding, not
during construction, cause otherwise every lens update would incur
significant overhead due to redundant serialization

WIP. Starting to remove owners from the StakePoolSnapShot

Reward computation is done

Fix and Improve Arbitrary for SnapShot

Move Stake definition to Stake module

Switch PoolMetadata.pmHash to ByteArray

...by using pack from MemPack.

This is expected to reduce memory fragmentation since ByteArray does not
use pinned memory.

Remove `sbsToByteArray` and `byteArrayToSbs` from `Mary.Value` in favor
of using `Data.MemPack.Buffer.byteArray{to|from}ShortByteString

Use `sizeofByteArray` from the primitive package in place of length for
this field.

Also, add an orphan `IsString` instance for `ByteArray`, and define
`NoThunks` for `PoolMetadata`.