Reverts a "flattening" feature in 2.1.7 that was causing issues with custom item data.
This release still has a known issue where some custom display name and lore might not be stored and read correctly when the server reboots. This is an inherent design flaw in how Spigot handles text formatting and will require significant rework to remedy the bug.
As with all releases, backup your data and test before installing on a production server. I can't stress this enough.