title: Behave: Accessing context.config variables outside of step definitions
body: <p>I am can't find out a way how to init my <code>ApiClient</code> with the value of <code>context.config.userdata['url']</code> from behave.ini </p>
  
  <p><strong>behave.ini</strong></p>
  
  <pre><code>[behave.userdata]
  url=http://some.url
  </code></pre>
  
  <p><strong>steps.py</strong></p>
  
  <pre><code>from behave import *
  from client.api_client import ApiClient
  
  # This is where i want to pass the config.userdata['url'] value
  api_calls = ApiClient('???') 
  
  
  @given('I am logged as "{user}" "{password}"')
  def login(context, user, password):
      context.auth_header = api_calls.auth(user, password)
  </code></pre>
  
  <p><strong>api_client.py</strong></p>
  
  <pre><code>class ApiClient(object):
  
      def __init__(self, url):
          self.url = url
  
      def auth(self, email, password):
          auth_payload = {'email': email, 'password': password}
          auth_response = requests.post(self.url + '/api/auth/session', auth_payload)
  
          return auth_response.text
  </code></pre>