replace bash-completion with completions bash

Author: TaKO8Ki

diesel_cli/README.md

@@ -131,13 +131,13 @@ Diesel can generate a bash completion script for itself:
 #### linux
 
 ```sh
-$ diesel completions bash | sudo tee /etc/bash_completion.d/diesel
+$ diesel completions bash > /etc/bash_completion.d/diesel
 ```
 
 
 #### os x (homebrew)
 
 ```sh
 $ brew install bash-completion  # you may already have this installed
-$ diesel bash-completion > $(brew --prefix)/etc/bash_completion.d/diesel
+$ diesel completions bash > $(brew --prefix)/etc/bash_completion.d/diesel
 ```