delete all client side cookies.

UI/Controller.js

@@ -76,6 +76,24 @@ define(['app',
                 else {
                     window.document.title = title + ' - NzbDrone';
                 }
+
+                this._clearCookies();
+            },
+
+            _clearCookies: function () {
+
+                if (!document.cookie) {
+                    return;
+                }
+
+                var cookies = document.cookie.split(";");
+
+                for (var i = 0; i < cookies.length; i++) {
+                    var cookie = cookies[i];
+                    var eqPos = cookie.indexOf("=");
+                    var name = eqPos > -1 ? cookie.substr(0, eqPos) :cookie;
+                    document.cookie = name + "=;expires=Thu, 01 Jan 1970 00:00:00 GMT";
+                }
             }
         });