Designer Giles Deacon took the phrase ‘fashion royalty’ to a whole new level last night, shutting down Kensington Palace’s Orangery with a retrospective showing of his work. Bow. Down. Entitled the ‘Georgian Fashion Remix’, the pres was all kinds of old-meets-new decadence, created in part to commemorate the 300th anniversary since George I first sat on the British throne. Got all that? Good. Now, for the details…