title: Mongodb : Check if a point is inside a stored polygon
body: <p>I'm new to the mongodb geolocation features.</p>
  
  <p>I stored some polygons that represent the country borders in a database along with the country name.
  Now what i would like to do is checking which country a point is in.
  For example if i give my own geolocation i would like to get the country where i am.</p>
  
  <p>Is there a way to do it with mongodb? Maybe with geoWithin?</p>
  
  <p>Thank you</p>