Release 2.1.0

Added

• Compatibility with the Burning Crusade Anniversary client (2.5.6)
• Item database covers the Burning Crusade item range

Changed

• Item ID ranges are measured against the client's own item table rather than
  estimated, which adds roughly 3800 items on Burning Crusade and extends the
  Classic range from 24283 to 24358
• Season of Discovery covers every seasonal item the client knows of, rather
  than stopping at 217704

Fixed

• Database updates no longer query the server for item IDs that do not exist.
  The existence check relied on C_Item.DoesItemExistByID, which answers true
  for every ID (WoWUIBugs #449), so roughly a third of each update was spent on
  items the client had never heard of

• Addon no longer errors on load now that GetAddOnMetadata and GetItemInfo
  only exist under C_AddOns and C_Item

• Chat integration works again on Classic Era 1.15.9, where the edit box
  handlers ChatEdit_OnTextChanged and ChatEdit_OnEditFocusLost were replaced
  by mixin methods

• Options panel registers with the Settings API, via updated Ace3 libraries