- add and handle layer 2 packet type correctly in data packets
- don't produce garbage packets if a packet could not be decoded or was not a
data packet
- handle beacon/connection request/connection parameters handshake
- digipeater cycle timeout does not reset beacon timer anymore. This prevented
any beacon transmission.
- Reset the connection timeout when empty packets are received
Instead, connection and digipeater now update a event code passed by reference
to the maintain() function. This was the only place where the callback was
called before.
Minor side effect: maintain must be called multiple times if multiple events
trigger at the same time.
This prevents loss of precision that occurs with double-precision floats if
timestamps become very large. Timestamps are already large if they contain a
UNIX time value (requires 60 bits; double has 53 bit resolution).
Thomas Kolb