Unable to create an admin menu link I am trying to create a menu link in Drupal 8. I am following this document: https://api.drupal.org/api/drupal/core!includes!menu.inc/group/menu/8

My module name is twitter_pull and I was able to create the path fine, and it loads a form on that page, I just can't get it display a menu link. I have tried flushing the caches but that didn't do anything.
Here is my code:

Inside my twitter_pull.routing.yml


twitter_pull.settings:
  path: 'admin/config/services/twitter-settings'
  defaults:
    _form: '\Drupal\twitter_pull\Form\TwitterSettingsForm'
  requirements:
    _permission: 'administer site configuration'


Inside my twitter_pull.links.menu.yml


twitter_pull.settings:
  title: 'Twitter settings'
  description: 'Twitter settings for your site'
  parent: system.admin_config_services
  route_name: twitter_pull.settings
  weight: 100
  #Use menu_name when you want to add your link to a non-system menu.
  #menu_name: devel
It looks like you are using an older version of Drupal core. Upgrade to one of the betas or the latest 8.0.x from Git and it should work fine.

In the latest versions the filenames have been changed, as reported in YAML files for menu links, contextual links, local tasks, and local actions have been renamed. 8.0.0-alpha14 is the first tagged release with the filename change.