Add option for Item Flavour Text with Styled Tooltips and Passive Tree Headers

[Blitz54]

Closing old PR for just flavour text as I can't be arsed trying to migrate the changes over cleanly.
This PR adds a toggle in the options menu for flavour text to be shown on Uniques, and also pretty up the item tooltip on hover, gems on hover, and passive tree nodes on hover.

• Separate headers for Normal, Magic, Rare, Unique, and Foil/Relic items. PoE2 only has one Foil so far, if they add more this could be updated, but it would at least show the normal Foil header for default.
• Item separators for each item rarity.
• Normal passive nodes, Notables, Keystones, and Jewel Sockets have a header image and use the normal item separator.
• Gems use a single line header image, and separator.
• Toggle is set to off for default.
• Tooltips function as they did with the toggle off. I hope, please test for yourself.

Issues

The crafting tooltip has all text left anchored, so it looks a little funny with the header on. I tried to center it, but the anchors are all whacky and I haven't quite figured that out yet.
Passive tree node text is also left aligned. Should be centred at some point, but it was breaking the oils display.

Before screenshot:

After screenshot: