[Bug fix][Enhance] Link Play Unlock Bug

- For Arcaea 6.12.0
- Support for "is_allow_marketing_email"
- Support for config "LOG_FOLDER_PATH" (Thanks to PR #234)
- Fix a bug about one song unlock bug in Link Play, due to wrong length of song unlock bytes.

latest version/database/init/packs.json

@@ -1072,11 +1072,29 @@
 			{
 				"id": "core_generic",
 				"type": "core",
-				"amount": 6,
+				"amount": 5,
 				"is_available": true
 			}
 		],
-		"orig_price": 600,
-		"price": 600
+		"orig_price": 500,
+		"price": 500
+	},
+	{
+		"name": "megarex",
+		"items": [
+			{
+				"id": "megarex",
+				"type": "pack",
+				"is_available": true
+			},
+			{
+				"id": "core_generic",
+				"type": "core",
+				"amount": 5,
+				"is_available": true
+			}
+		],
+		"orig_price": 500,
+		"price": 500
 	}
 ]