title: MongoDB - $geoWithin query using $polygon or $geometry gives different result
body: <p>Using MongoDB 3.2 i'm trying to use 2dsphere queries on a collection of Points.</p>
  
  <p>Lets say i have à collection <strong>cust_5_abcd</strong> with a 2dsphere index on <strong>the_geom</strong> field.</p>
  
  <p>Add a geometry in the collection : </p>
  
  <pre><code>db.cust_5_abcd.insert({
  "chps0" : "Texte d'une ligne",
  "the_geom" : {
      "type" : "Point",
      "coordinates" : [ 
          1.032715, 
          40.380028
      ]
  }})
  </code></pre>
  
  <p>Now i'm trying to query this Point using $geoWithin to get all data inside a specific Polygon. This is where i'm getting different result if i use <strong>$geometry</strong> with the GeoJSON definition , or with <strong>$polygon</strong> and the strict coordinates. Maybe something in the documentation is missing or something i misunderstood.</p>
  
  <p>With <strong>$geometry</strong> gives NO result:</p>
  
  <pre><code>db.cust_5_abcd.find(  { the_geom: 
   { $geoWithin: 
          { $geometry: 
              {       
                  "type": "Polygon", 
                  "coordinates": [ 
                      [ 
                          [ -16.237793, 40.162083 ], 
                          [ -16.237793, 51.835778 ], 
                          [ -13.776855, 51.835778 ], 
                          [ -13.776855, 41.426253 ], 
                          [ 14.765625, 41.426253 ], 
                          [ 14.765625, 40.162083 ], 
                          [ -16.237793, 40.162083 ] 
                  ] 
                  ]
              } 
          } 
      } 
  })
  </code></pre>
  
  <p>With <strong>$polygon</strong> returns my Point :</p>
  
  <pre><code>db.cust_5_abcd.find( { the_geom: 
   { $geoWithin: 
          { $polygon:
                      [ 
                          [ -16.237793, 40.162083 ], 
                          [ -16.237793, 51.835778 ], 
                          [ -13.776855, 51.835778 ], 
                          [ -13.776855, 41.426253 ], 
                          [ 14.765625, 41.426253 ], 
                          [ 14.765625, 40.162083 ], 
                          [ -16.237793, 40.162083 ] 
                  ]                 
          } 
      } 
  })
  </code></pre>