Fix tooltip positioning and size for multi-column tooltips

[majochem]

Description of the problem being solved:

1. Hover tooltips that require multiple columns (usually item comparisons), do not always correctly reposition to the maximum amount of content on screen, which hides a lot of valuable information

2. Multi-column tooltips generally often waste horizontal space, because they inherit the width from the first columns, which can be much wider, e.g. for unique items with long mods

This PR makes two changes to address that behavior:

1. Tooltips are moved to the left as much as necessary (and possible) in order to fully fit into the viewPort
2. Any additional columns beyond the first, now recalculate their required width in order to waste less space

Steps taken to verify a working solution:

• I tested this on my own monitors (one 3440x1440 and two 1920x1080) at various UI scaling options (both OS and PoB internal scaling), as well as individually resized windows and encountered no issues
• Having said that, I haven't done a lot of UI PRs, so there might be some niche edge cases that I overlooked

Limitations:

• This PR doesn't (yet) solve the issues of too many columns to physically fit on the screen. I am looking into that, but will likely put it into separate PRs and in the meantime it does at least mitigate the issue somewhat.

Link to a build that showcases this PR:

https://pobb.in/P0OpEhfbjoHc
(Just random build, not specifically generated for this issue)

Before vs After Screenshot 1:

Hover tooltip cut off

Repositioned and no longer cut off

Before vs After Screenshot 2:

Static tooltip wasting space (trying to add Abberath's Hooves)

Second column only as wide as needed for the text