Allow user to set static page before saving
Allow user to set static page before saving

fixes #1350
- jQuery event.preventDefault() stops the user from selecting the checkbox

kevinansfield/Ghost-Admin,dbalders/Ghost-Admin,JohnONolan/Ghost-Admin,acburdine/Ghost-Admin,TryGhost/Ghost-Admin,airycanon/Ghost-Admin,dbalders/Ghost-Admin,acburdine/Ghost-Admin,TryGhost/Ghost-Admin,kevinansfield/Ghost-Admin,airycanon/Ghost-Admin,JohnONolan/Ghost-Admin