Zhang Huan is the type of artist whom many outside the rarefied world of performance art label a crackpot. He has covered his naked body in honey and fish oil and sat in a public toilet, attracting flies. For his piece “Zhang Huan: Seeds of Hamburg,” documented in a series of photographs on view at the Museum of Fine Arts, he coated himself with honey and birdseed and closed himself in a cage with 28 doves. Under rainy skies Monday evening in “Zhang Huan: My Boston,” a live performance, he had himself buried under a pile of books.