It’s been a good week for speed metal fans in Belfast with not one but two Slayer gigs, followed by tonight’s long awaited show from Noo Yoik’s nonpareils of noise, Anthrax. That’s 50% of the ‘Big Four’ of thrash on the same modestly sized Limelight stage, while Metallica are headlining Glastonbury and Megadeth are off, I don’t know, probably offending a minority group. Yea, verily, it is the season of metal. If the audience are beginning to feel a little spoilt they certainly don’t show it, piling into the venue as soon as doors open and readily assuming the position…