title: Cannot acces variable from angular provider inside angular config
body: <p>I'm new to angular, so I'm pretty sure it is a stupid question, but I failed to figure this out myself.
  I have an app in which I have provider to get token from cookies using ngCookies, and I need to access it from inside app.config. I've tried several methods, but all I can get is service code, not a returned variable. What am I doing wrong?</p>
  
  <pre><code>var app = angular.module('appClient', [
    'ngCookies'
  ]);
  
  app.provider('getToken', function getTokenProvider() {
    this.$get = ['getTokenService', function(getTokenService, $cookies) {
      var token = $cookies.get('token');
      return token;
    }]
  });
  
  app.config(function ($resourceProvider, $httpProvider, getTokenProvider) {
    var token = ? //need to get token from getTokenProvider here
    $httpProvider.defaults.withCredentials = false;
    $resourceProvider.defaults.actions = {
      save: { method: 'POST', params: { token: token } },
      get: { params: { token: token } },
      query: { params: { token: token }, isArray: true }    
    };
  });
  </code></pre>