Add showcased Mercenaries of Trarthus uniques

[Paliak]

Description of the problem being solved:

Not sure if this is worth a PR but i added the showcased uniques to New.lua and started working on parsing for the new mods:

• [ ] Trigger Level 20 Starfall on Melee Critical Strike This will require gem data to implement correctly.
• [ ] Grants a random Divination buff for 20 seconds when used List of available mods is currently unknown
• [x] Gain Arcane Surge when you use a Movement Skill
• [x] Increase to Cast Speed from Arcane Surge also applies to Movement Speed
• [x] Armour from equipped shield is doubled
• [x] Gain no armour from equipped body armour This assumes that the base value is nullified meaning that you still get armour with this mod when using Iron Reflexes. I tried implementing this using a "MORE" mod but that caused issues with Iron Reflexes.
• [x] Non-instant Warcries you use yourself have no Cooldown
• [x] Warcries have an additional Life Cost equal to 15% of your Maximum Life
• [x] Damage penetrates Fire Resistance equal to your overcapped Fire Resistance
• [x] Take 449 Fire Damage when you use a Skill

This pr also makes it so that doubling mods (including Unbreakable and Oath of the Maji) do not affect "per (%d+) armour on equipped shield" style mods (only the value on the actual item is taken into consideration). https://github.com/PathOfBuildingCommunity/PathOfBuilding-PoE2/pull/1095 has been ported to POB1 to allow for better piece wise parsing of "doubled" mods.