zx81_cass.xml: Added 31 items (30 working). (#12858)

New working software list items (zx81_cass.xml)
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Ant Attack [Bob's Stuff]
Avalanche [Revival Studios]
Argolath [Spectrum Computing]
Bar Billards [Spectrum Computing]
Boulder Logic [Bob's Stuff]
Bigg Oil [Spectrum Computing]
Budget Familial [Spectrum Computing]
Budget Familial (alt) [Spectrum Computing]
Casse-Briques + Pendu [Team Zeddy, Planeta Sinclair]
Chiromancie [Spectrum Computing]
Crozxy Road [Bob's Stuff]
Domin8tr1s [Bob's Stuff]
Down! [Revival Studios]
Impact [Bob's Stuff]
Jogos 3 [Planeta Sinclair]
Mayhem [Revival Studios]
Miner Man [Bob's Stuff]
Noir Shapes [Bob's Stuff]
One Little Ghost [Bob's Stuff]
Pandemic [Bob's Stuff]
Panique [Team Zeddy, Planeta Sinclair]
Quack! [Bob's Stuff]
Rebound [Bob's Stuff]
Rigel [Spectrum Computing]
Shrooms [Bob's Stuff]
Stairrunner [Revival Studios]
Steps [Bob's Stuff]
U-Bend [Bob's Stuff]
Virus [Bob's Stuff]
ZXagon [Bob's Stuff]

New software list items marked not working (zx81_cass.xml)
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3D 3D! [Spectrum Computing]

Removed sets - duplicate, same as parent (zx81_cass.xml)
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The Flight Simulator (Timex)
Flug-Simulation

Author: ArcadeShadow