XMage: Prerelease Promo cards

[luziferius]

Stamped cards given as a Prerelease event promo are grouped in the PTC pseudo-set in XMage. See the source code here: https://github.com/magefree/mage/blob/master/Mage.Sets/src/mage/sets/PrereleaseEvents.java

TappedOut CSV exports contain this information in the Foil column by indicating the foiling to be pre.

To Support Prerelease promos:

• Update the Card data class. Instead of a foil boolean, use a speciality enumeration.
  

  MTGDeckConverter/MTGDeckConverter/model.py

  Lines 26 to 37 in bdd0341

  	@dataclass
  	class Card:
  	"""This is a single MTG card"""
  	english_name: str = None
  	set_abbreviation: str = None
  	# Most cards have integer collector numbers, but some require further disambiguation in the form of appended letters
  	# To support collector numbers like "86a", the collector number is handled as a string.
  	collector_number: str = None
  	# Returned by TappedOut.
  	language: str = "EN"
  	foil: bool = False
  	condition: str = None

• Update the CSV parser to set the card speciality instead of the foil boolean.
• Include a translation layer in the XMage exporter that looks at the card and replaces the set abbreviation with PTC if the card is a Prerelease promo.