Ah, festivals. Around these parts the very word conjures up images of wet weekends with wellies, mud, overpriced beer, flooded tents and a bunch of rowdy twats in the campsite who “only came here to see David Guetta.” Sure, there are more than enough decent acts to be seen, but precious few of them can stave off the sinking feeling that spreads throughout the crowd when it senses the pitter-patter of rainfall as the opening song rings out. Which is why The Thin Air has made an executive decision and flown out to the northern Portuguese city of Porto for…