Add a UI to easily create scaffolding for new modules (including hooks, plugins, permissions etc.) NB: first, you need to download drupal-code-builder from GitHub and place it in a /libraries top-level directory (see module builder's README.txt). You can preview and edit the output files before writing to disk - and each module's configuration is saved as a node, so you can add another hook etc. at a later date, regenerate the files and copy/paste the extra things you need. Video walkthrough.
Tested by me
Drupal 8 support