Call To*InboundLaneApi::message_details() with batched messages (#1545)

* generated_message_details() -> Simplifications

- avoid using a HashMap for `messages_to_refine`. It seems that a vec is
  enough
- minimize the number of conversions between `OutboundMessageDetails` and
  `MessageDetails`
- use references where possible in order to minimize the number of
  intermediary Vecs
- simplify `make_message_details_map()` logic, reduce its scope and rename
  it to `validate_out_msgs_details()`

Signed-off-by: Serban Iorga <serban@parity.io>

* Define typed_state_call()

Signed-off-by: Serban Iorga <serban@parity.io>

* Call To*InboundLaneApi::message_details() with single messages

Signed-off-by: Serban Iorga <serban@parity.io>

* Call To*InboundLaneApi::message_details() with batched messages

Signed-off-by: Serban Iorga <serban@parity.io>

* validate_out_msgs_details() -> change check

* Define split_msgs_to_refine()

Signed-off-by: Serban Iorga <serban@parity.io>

Signed-off-by: Serban Iorga <serban@parity.io>