I've been setting up a new Ubuntu 16.04 laptop for Drupal development. I had trouble installing Drush using Composer, but eventually got things working. Today, while setting up Drush tab completion, I discovered five instances of drush.complete.sh:
$ locate drush.complete.sh
*cough* I think I need to clean things up and start from scratch. How can I correctly uninstall all these Drush instances?