feat: new Web UI build system

- use generator-gulp-angular by @swiip
- remove old static file

webui/src/app/core/providers.resource.js

@@ -0,0 +1,13 @@
+(function () {
+  'use strict';
+
+  angular
+    .module('traefik.core.provider', ['ngResource'])
+    .factory('Providers', Providers);
+
+    /** @ngInject */
+    function Providers($resource) {
+      return $resource('/api/providers');
+    }
+
+})();