Dragan Dosen 0b85ecee53 MEDIUM: logs: add a new RFC5424 log-format for the structured-data
This patch adds a new RFC5424-specific log-format for the structured-data
that is automatically send by __send_log() when the sender is in RFC5424
mode.

A new statement "log-format-sd" should be used in order to set log-format
for the structured-data part in RFC5424 formatted syslog messages.
Example:

    log-format-sd [exampleSDID@1234\ bytes=\"%B\"\ status=\"%ST\"]
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