force rounding to integer the result of map.getZoom() when calculating the map data zoom

it's not something that sould happen, but it's been seen on mobile (#271) - this should eliminate the issues with portal data this causes

code/utils_misc.js

@@ -247,6 +247,9 @@ window.renderLimitReached = function(ratio) {
 window.getPortalDataZoom = function() {
   var z = map.getZoom();
 
+  // on mobile (at least), the map zoom has been non-integer occasionally. fix it.
+  z = Math.floor(z);
+
   // limiting the mazimum zoom level for data retrieval reduces the number of requests at high zoom levels
   // (as all portal data is retrieved at z=17, why retrieve multiple z=18 tiles when fewer z=17 would do?)
   // very effective along with the new cache code

plugins/show-more-portals.user.js

@@ -2,7 +2,7 @@
 // @id             iitc-plugin-show-more-portals@jonatkins
 // @name           IITC plugin: Show more portals
 // @category       Tweaks
-// @version        0.1.0.@@DATETIMEVERSION@@
+// @version        0.1.1.@@DATETIMEVERSION@@
 // @namespace      https://github.com/jonatkins/ingress-intel-total-conversion
 // @updateURL      @@UPDATEURL@@
 // @downloadURL    @@DOWNLOADURL@@
@@ -29,6 +29,9 @@ window.plugin.showMorePortals.setup  = function() {
   window.getPortalDataZoom = function() {
     var mapZoom = map.getZoom();
 
+    // on mobile (at least), the map zoom has been non-integer occasionally. fix it.
+    z = Math.floor(z);
+
     // yes, it is possible to increase this beyond "+1" - however, that will end up producing a rediculous number
     // of requests to the Niantic servers, giving many request failed errors/tile timeouts
     // (every increase by one requests four times as many data tiles)