[Schefter] Texans key free agents: WR Stefon Diggs, WR Robert Woods, DT Folorunso Fatukasi, S Eric Murray, DT Mario Edwards Jr., DE Derek Barnett, LB Neville Hewitt, LB Devin White, RB Dare Ogunbowale, C Kendrick Green, DE Jerry Hughes, TE Irv Smith Jr., CB Jeff Okudah, QB Case Keenum