Fix various template warnings (#32)

- Missing :
- Deprecated =
- Not valid color name
- Must always return statement

data/magic-m15-GoodBad.mse-style/style

@@ -141,7 +141,7 @@ styling field:
 	name: promo
 	description: Is this card a promo card, with the "P" rarity?
 	initial: no
-styling field
+styling field:
 	type: boolean
 	name: masterpiece
 	description: Is this card a Masterpiece?
@@ -304,9 +304,7 @@ card style:
 			name: MPlantin
 			italic name: MPlantin-Italic
 			size: 10
-			color: if (card.color == "black" )
-				then "white"
-				else "black"
+			color: { if card.card_color == "black" then "white" else "black" }
 		symbol font:
 			name: { styling.text_box_mana_symbols }
 			size: 11.5