MEDIUM: stats: make stats_dump_li_stats() use stats fields for HTML dump

MEDIUM: stats: make stats_dump_li_stats() use stats fields for HTML dump

The conversion still requires some elements which are not present in the
current fields :
  - the HTML status may emit "WAITING"/"OPEN"/"FULL" while the CSV format
    doesn't propose "WAITING", so this last one will have to be added.

  - the HTML output emits the listening adresses when the ST_SHLGNDS flag
    is set but this address field doesn't exist in the CSV format

  - it's interesting to note that when the ST_SHLGNDS flag is not set, the
    HTML output doesn't provide the listener's ID while it's present in the
    CSV output accessible from the same interface.