title: search with marker and zoom , fit map on near the marker with gmap3
body: <p>i use gmap3 plugin for show result in google map 
  have text box field , when someone type for example "new york" many marker in the new york town , i want map zoom and fit in new york  and show all of the marker in this place?
  how to can do it?
  for show to your what i want look at this site : padmapper.com</p>
  
  <p>and this is my code :</p>
  
  <pre><code>$(function(){
             $("#main-map").gmap3({
        map:{
          options:{
            center:["newyork"]
          }
        },
        marker:{
          values:[
            {latLng:[48.8620722, 2.352047]},
            {address:"86000 Poitiers, France"},
            {address:"66000 Perpignan, France"}
          ],
        }
      });
      $('#ok').click(function(){
        var addr = $('#Address').val();
        if ( !addr || !addr.length ) return;
        $("#main-map").gmap3({
          getlatlng:{
            address:  addr,
            callback: function(results){
              if ( !results ) return;
              $(this).gmap3({
                marker:{                              
                  latLng:results[0].geometry.location,
                  map:{
                      options:{
                      center: addr ,
                      zoom: 12
                      },
                    center: addr
                  }
                }
              });
            }
          }
        });
      });
  
      $('#Address').keypress(function(e){
        if (e.keyCode == 13){
          $('#ok').click();
        }
      });
    });
  </code></pre>
  
  <p>and html code</p>
  
  <pre><code>    &lt;div id="main-map"&gt;
          &lt;/div&gt;
      &lt;input type="text" placeholder="City, Address, or Zip" name="goToAddress" style="margin-left:5px; width:215px;" id="Address"&gt;
  &lt;button id="ok" type="button"&gt;Go&lt;/button&gt;
  </code></pre>