Update README.md with one more .zimrc example

and hopefully make it clear that the completion module is optional, and
just for users that prefer our predefined configuration instead of their
own set up calling compinit directly.

README.md

@@ -139,8 +139,17 @@ You can start with just:
 zmodule zsh-users/zsh-syntax-highlighting
 zmodule zsh-users/zsh-autosuggestions
 ```
-Or, if you also want to use completions:
+
+If you also want one of our prompt [themes]:
+```
+zmodule asciiship
+zmodule zsh-users/zsh-syntax-highlighting
+zmodule zsh-users/zsh-autosuggestions
+```
+
+If you want to use our [completion] module too, instead of using `compinit` directly:
 ```zsh
+zmodule asciiship
 zmodule zsh-users/zsh-completions --fpath src
 zmodule completion
 zmodule zsh-users/zsh-syntax-highlighting