Fix map markers navigation for keyboard users

By using the bindPopup function instead of the click event
popups work when using the keyboard.

Note that now we are loading all the map markers in the first
request in a single query to the database (needed when there
is a lot or markers to show). Because of that we removed the
AJAX endpoint.

app/assets/javascripts/map.js

@@ -172,7 +172,7 @@
           if (App.Map.validCoordinates(coordinates)) {
             marker = createMarker(coordinates.lat, coordinates.long);
             marker.options.id = coordinates.investment_id;
-            marker.on("click", App.Map.openMarkerPopup);
+            marker.bindPopup(App.Map.getPopupContent(coordinates));
           }
         });
       }
@@ -217,19 +217,8 @@
 
       polygon.addTo(map);
     },
-    openMarkerPopup: function(e) {
-      var marker = e.target;
-      $.ajax("/investments/" + marker.options.id + "/json_data", {
-        type: "GET",
-        dataType: "json",
-        success: function(data) {
-          e.target.bindPopup(App.Map.getPopupContent(data)).openPopup();
-        }
-      });
-    },
     getPopupContent: function(data) {
-      return "<a href='/budgets/" + data.budget_id + "/investments/" + data.investment_id + "'>" +
-             data.investment_title + "</a>";
+      return "<a href='" + data.link + "'>" + data.title + "</a>";
     },
     validZoom: function(zoom) {
       return App.Map.isNumeric(zoom);