0.4.0

Fixed

• Sanctorale#replace saving the supplied array as part of
  the internal data structures (and thus allowing their -
  usually unintentional - modification by external code)
• Calendar unintentionally modifying Sanctorale internal data
  when handling optional memorials
• errors in English ordinals greater than 10 ("21th" -> "21st" etc.)
• Ranks::FERIAL.memorial? wrongly returning true
• rank of All Souls fixed in all data files

Added

• support for transfer of Epiphany, Ascension and Corpus Christi
  to a Sunday (GNLYC 7)
• General Roman Calendar in French and French localization
  (by Azarias Boutin @AzariasB)
• PerpetualCalendar
• Season#name, Colour#name - localized human-readable names

Changed

• interface for Temporale extensions changed completely:
  extensions are self-contained, isolated; their sole responsibility
  is to yield data
• Calendar stripped of the ability to create new instances
  with the same settings:
  • Calendar#pred and #succ removed
  • Calendar.new receives Temporale instance
    (instead of a temporale factory)
• Calendar#day raises RangeError if the day is earlier than
  1st January 1970 (day of introduction of the implemented calendar
  system)
• Temporale::Dates.easter_sunday doesn't return Julian calendar
  Easter date for years <= 1752 (this library isn't intended to be used
  for years earlier than 1970)
• Day#== and Calendar#== test object contents, not identity
• Temporale::Dates.body_blood renamed to .corpus_christi
• Sanctorale#freeze freezes also the internal data structures
• Calendar#freeze freezes contained Temporale and Sanctorale
• seasons and colours indexed by their symbols, not by index number -
  e.g. Seasons[:lent], Colours[:violet]
• Calendar#celebrations_for made private