Jeff Fairburn, group md of Persimmon, will become the housebuilder's new ceo following the announcement that Mike Farley will retire at the company's AGM in April. Farley will step down after seven years in the top post, and almost 30 years at Persimmon. Fairburn joined Persimmon in 1989, and was appointed group md in January 2012. At Galliford Try, Ian …