The Old Globe Theatre has mounted a stately production of George Bernard Shaw’s best comedy – Pygmalion – on the occasion of the play’s centenary. (It was first performed, in German, at Vienna for reasons both complicated and uninteresting.)   Most of the Globe’s strengths are in evidence. Alexander Dodge’s set is gorgeous and witty, packed with tactile clutter and boasting a handsome parquet floor, which revolves (usually) when needed. The Robert Morgan costumes are precisely right, Philip S. Rosenberg has frosted everything with appropriate illumination and Mark Bennett has provided crisp musical punctuation with custom-made noodlings in the style…