Remove uses of SerializedValues from public API

[Lorak-mmk]

Those uses are a leftover from previous API and should be removed - most likely replaced with impl SerializeRow

Usages to be removed:
https://docs.rs/scylla/latest/scylla/transport/partitioner/fn.calculate_token_for_partition_key.html
https://docs.rs/scylla/latest/scylla/transport/struct.ClusterData.html#method.compute_token
https://docs.rs/scylla/latest/scylla/transport/struct.ClusterData.html#method.get_endpoints

[Lorak-mmk]

I think it has dependency on #691
The reason is that we need to create RowSerializationContext, which operates on ColumnSpec (which contains ColumnType), using Table, containing pub columns: HashMap<String, Column>, - and Column contains CqlType.