Death Wish (Maw of Mischief) rework

[Lothrik]

This adds a minion selector (currently only used by Death Wish), separates the spell and minion explosion components of Death Wish, add some new functionality to the config tab. There's also a bit of miscellaneous code clean up in here (formatting mostly).

Fixes #2372.

Link to a build that showcases this PR:

https://pobb.in/VcllNw4VS8tM

After screenshot:

[Lothrik]

Converting this PR to draft, as after reviewing several usability issues came up that need to be addressed.

Two notable examples are:

• The minion selector list does not update automatically when minions change (which isn't ideal but can be worked around), and can get stuck in an invalid state if only one minion is present in the build (which is very problematic as it will persist until you restart PoB).
• Node tooltip DPS estimates don't display correctly if Death Wish Full DPS calculates before minion life is recalculated. Manipulating the order Full DPS processes skills (forcing Death Wish to run last) should fix this fairly easily.

Also: Death Wish should likely have Full DPS force enabled as it cannot currently calculate its DPS correctly without it, due to the reliance on minion life calculations from other skills.