don't rely on `hasOwnProperty` to exist

from MDN:
JavaScript does not protect the property name hasOwnProperty; thus, if the possibility exists that an object might have a property with this name, it is necessary to use an external hasOwnProperty to get correct results

lib/object-patch.js

@@ -11,7 +11,7 @@ Object.get = function(obj, pathstr) {
 
   for (var i = 0; i < path.length; i++) {
     var key = path[i];
-    if (!result || !result.hasOwnProperty(key)) {
+    if (!result || !Object.prototype.hasOwnProperty.call(result, key)) {
       return undefined;
     } else {
       result = result[key];

lib/routes/avatars.js

@@ -55,7 +55,7 @@ module.exports = function(req, callback) {
   var userId = (req.url.path_list[1] || "").split(".")[0];
   var size = parseInt(req.url.query.size) || config.avatars.default_size;
   var def = req.url.query.default;
-  var overlay = req.url.query.hasOwnProperty("overlay") || req.url.query.hasOwnProperty("helm");
+  var overlay = Object.prototype.hasOwnProperty.call(req.url.query, "overlay") || Object.prototype.hasOwnProperty.call(req.url.query, "helm");
 
   // check for extra paths
   if (req.url.path_list.length > 2) {

lib/routes/renders.js

@@ -64,7 +64,7 @@ module.exports = function(req, callback) {
   var userId = (req.url.path_list[2] || "").split(".")[0];
   var def = req.url.query.default;
   var scale = parseInt(req.url.query.scale) || config.renders.default_scale;
-  var overlay = req.url.query.hasOwnProperty("overlay") || req.url.query.hasOwnProperty("helm");
+  var overlay = Object.prototype.hasOwnProperty.call(req.url.query, "overlay") || Object.prototype.hasOwnProperty.call(req.url.query, "helm");
 
   // check for extra paths
   if (req.url.path_list.length > 3) {