added two decks posted by Old Nick on the forum

release/Magarena/decks/Black_and_White.dec

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+# 5 creatures
+4 Deathbringer Liege
+2 Mourning Thrull
+2 Nip Gwyllion
+2 Perimeter Captain
+4 Souls of the Faultless
+
+# 3 spells
+2 Debtors' Knell
+4 Unmake
+4 Vindicate
+
+# 4 lands
+4 Godless Shrine
+4 Isolated Chapel
+4 Plains
+4 Swamp
+
+>A simple Black/White removal deck, with Deathbringer Liege as the centerpiece

release/Magarena/decks/Haunted_Humans.dec

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+# 7 creatures
+2 Champion of the Parish
+2 Doomed Traveler
+2 Fiend Hunter
+2 Geist of Saint Traft
+2 Gideon's Lawkeeper
+2 Hero of Bladehold
+2 Mirran Crusader
+
+# 4 spells
+2 Angelic Destiny
+4 Honor of the Pure
+2 Negate
+2 Oblivion Ring
+
+# 3 lands
+4 Glacial Fortress
+8 Plains
+4 Seachrome Coast
+
+>A white human based deck with a small amount of blue worked in.