Silenced Pistols for BDv21 Gold addon

Credit to: @ProfessorExistential for the Tomtefars+EWM+ManofHell pack that the pistol was initially from.
(Now which one of the many sources he used that it came from I am not sure, at least three of them have full mods with silenced pistols and duals in them now.)
I just backported it into BDv21 Gold as a standalone addon & made some tweaks and fixes along the way as I playtested.

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HOW TO USE
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To use this weapon, -Reload- while the magazine is full to attach/detach the silencer,

Use -Dual Wield/Weapon Special- to dual wield it (Must have picked up another pistol from an enemy),

And use -AltFire- to switch between burst and single-shot.

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Additional changes from the source material:
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The -Kick- key originally added and removed the silencer as well as attempting to reload while full,
that's changed so you may now give the slayer's mighty foot to any demon you please with these guns out.
The Dual Silenced pistols wouldn't switch into at all either, but through some A_GiveInventory trickery, this issue was resolved too.

Not only did many of its sprite frames still used the unsilenced PI2 sprites, which were incorrect,
the burstfire function for the dual silenced mode were commented out entirely.
I have restored the burstfire and set the correct sprites. All the functions from the original mod that were not a part of Brutal Doom Gold (code related to Quick Axe, Quick Chainsaw, laser sight, and ice bullets) were stripped out, which caused yet another problem that led to a bunch of reserve ammo being dumped out whenever the player reloaded with ammo still in the magazine, which took longer to narrow down.
Some changes to InsertBullets2 and InsertBullets2B fixed that. I also added the missing +WEAPON.NOALERT flag to the dual silenced pistols so that it will actually work as silenced.

I have also taken the liberty of rebalancing the damage output of the weapon for both silenced and unsilenced modes, made some tweaks to the burst fire timing to make it a little more controllable, as well as found a better audio sample for the silenced fire & adjusted its volume.

Now go pop demon heads all sneaky-beaky like while their buddies standing next to them convince themselves very hard that it was just the wind.

EDIT1: Proofread README, gunsmoke reimplemented for silenced akimbos, and placed it in the correct addon category. (My apologies for this not being up sooner, but it was my fault for choosing the New Years holiday out of all times to originally upload it, the time when nobody was around to run it through the authorization process.)