on schema update, festive variants are linked. on content injection, if if finds a festive variant, it adds price rows for Festive and Strange Festive.
price update time was not properly serialized as a number like the schema was, and led to dates being stored as empty objects. UI code also did not check if date was NaN, and rendered "invalid date" instead.
Changed schema lookups to prioritize non-stock/non-decorated item defindexes when names collide
Modified unit tests to include example (stock Flame Thrower)
