Added membersAutoLogin labs flag
Added membersAutoLogin labs flag

refs https://github.com/TryGhost/Team/issues/1067

- To be used whilst developing the auto-login functionality so we can
  test this on production sites.

TryGhost/Ghost,TryGhost/Ghost,TryGhost/Ghost,ErisDS/Ghost,ErisDS/Ghost,e10/Ghost,e10/Ghost,ErisDS/Ghost