GitHub cofounder and CEO Chris Wanstrath Flickr/by DaveFayram Cofounder CEO Chris Wanstrath, with support from the board, is radically changing the company's culture: Out with flat org structure based purely on meritocracy, in with supervisors and middle managers. This has ticked off many people in the old guard.Its once famous remote-employee culture has been rolled back. Senior managers are no l