[TODO] (Breaking) changes for the 1.19 update

[x] Remove deprecated Tooltips API class (replaced by TooltipBuilder)
[x] Remove other deprecated methods
[ ] Implement IAdvancedItem into AdvancedArmorItem and replace the current hooks with the ones provided by the interface
[x] Move registry classes from core to core.registry
[x] Move utility classes from core to core.util
[x] Move ModTooltips to core.util and remove deprecated methods within the class
[x] Completely remove content package and classes within the package
[x] Rename subfolders of assets/textures to be non-plural

Autovw / AdvancedNetherite