added getAllHeroes()
added getHeroesPlayedAs and getHeroesNotPlayedAs

added getHeroesPlayedAs and getHeroesNotPlayedAs.  The two functions
return lists of heroIDs when given playerIDs, and (optionally)
matchdetails.  getHeroesNotPlayedAs also takes a localized parameter to
return localizednames instead of heroIDs.
changed getAllMatches to use date_max

changed getAllMatches to use date_max as the url parameter instead of
start_at_match_id, which means that getAllMatches can now return all
matches by a player instead of capping at 500.