The main repository of lib60870 has merged the pkg-config file fork used
until now.

Use the main lib60870 instead of my fork for 'packaging/deps.sh'.

Fixes an issue where global interrogation would not respond when the
configured asdu_type includes a timestamp.

Fixes incorrect configuration asdu_type_id strings.

Fix an issue where multiple connections may be established in single
redundacy mode which causes the message queue to corrupt on shutdown.

If `duplicate_ioa_is_sequence` is enabled in the `out` section of the
node config, a duplicate ioa will be increased. This only works for
subsequently defined signals with the same IOA.

Remove "this->" and add spaces behind commata.

ASDUs have a limited capacity, this creates multiple ASDUs if a single
one is not able to hold all sample values.

Single redundancy implies a single queue of messages which buffers
messages until a client connects. In contrast to the previous multiple
redundancy group mode, this mode can only accept one client at a time.

- Move lambde `fill_asdu` to dedicated function SlaveNode::fillASDU.
- Remove "-slave" suffix from node name so it does not mess up logging
  and help message.
- Expose queue sizes settings in config

Rename `SlaveNode::out` to `SlaveNode::output`, because base class
`Node` and derived class `SlaveNode` both defined a member `out`.

the cause of transmission and qualifier of interrogation share the numeric meanings,
e.g the QOI for "station" equals the COT for "interrogated by station".

Thus the previous code was not wrong, but still confusing to the reader.

Features:
- respond with last value when interrogated
- log connection events
- allow IEC60870-5 TypeIDs in the config file (as "asdu_type_id")

Fixes:
- wrong handling of MeasuredValueNormalized

This allows sending periodic signals using the new node.

The node does not yet support...

...proper logging of ASDUs.
...providing data on Global Interrogation.
...buffering setValue commands to read values which have been sent to slave.
...clockSync commands, what would the proper handling be?