GH-46: Clarify Drupal version in ddev config example

- update setup command to use --project-type=drupalN
- add note that N is the Drupal version number

Refs: README.md

Author: hkirsman

README.md

@@ -13,14 +13,16 @@ scripts to enhance your Drupal development workflow.
 ### Steps
 
 1. Initialize your Drupal project. Project name parameter is optional, but
-it's advisable to use domain name as your project name as that's used for
-the subdomain of ddev.site eg if project name is example.com, then localhost
-URL will become example.com.ddev.site.
+   it's advisable to use domain name as your project name as that's used for
+   the subdomain of ddev.site eg if project name is example.com, then localhost
+   URL will become example.com.ddev.site.
 
    ```bash
-   ddev config --project-type=drupal --docroot=web --project-name=example.com
+   ddev config --project-type=drupalN --docroot=web --project-name=example.com
    ```
 
+   where N is the version of Drupal.
+
 2. Install Wunderio DDEV Drupal as a DDEV add-on and restart DDEV:
 
    ```bash