def validate!(options={})
      begin check_ranks rescue rerank end if options[:rerank]
      check_players
      check_rounds
      check_dates
      check_teams
      check_ranks(:allow_none => true)
      check_type(options[:type]) if options[:type]
      true
    end
def validate!(options={})
      begin check_ranks rescue rerank end if options[:rerank]
      check_players
      check_rounds
      check_dates
      check_teams
      check_ranks(:allow_none => true)
      check_type(options[:type]) if options[:type]
      true
    end
Raise an exception if a tournament is not valid. The _rerank_ option can be set to _true_
 to rank the tournament just prior to the test if ranking data is missing or inconsistent.