Add new start option "-D".

Add new start option "-D".
Change the vaild range of client_idle_limit_in_recovery (Now -1 became valid).
Add new pgpool-II parameters for pgpool-II 2.4:
  master_slave_sub_mode, delay_threshold,
  log_standby_delay, debug_level, failover_if_affected_tuples_mismatch
Fix some table headers to use <thead></thead>