title: reauth every 7 days with the google calender api
body: <p>google calender api limits access to 7 days.</p>
  <p>So every week i have to do the process over agen to get access to my calender.
  Google limits token for 7 days, then you have to do it all over agen witch is frustrating.</p>
  <p>I've googled about this issue, and no one seems to know anything about it.</p>
  <p>why cant i have permanent access to my calender with gcalcli without having to reauthenticate every week?</p>