Everyman, LiverpoolNathan Powell sets out his stall with a crowd-pleasing play about intergenerational tensions in a Caribbean cafe This play by Nathan Powell, appointed creative director at Liverpool Everyman and Playhouse last year after Suba Das's departure, is not a tightly structured, slick affair. But, directed by Amanda Huxtable, it is enormous fun, full of heart and undeniably entertaining. If this first play…