Updates docs for open source and Alley developers

[mogmarsh]

Description of the documentation inaccuracy

• Update READMEs on this project as well as https://github.com/alleyinteractive/create-wordpress-plugin and https://github.com/alleyinteractive/create-wordpress-theme
• Update internal Alley Documentation

here's the command to create a theme: composer create-project alleyinteractive/create-wordpress-theme themes/{slug}
and the command to create a plugin composer create-project alleyinteractive/create-wordpress-plugin plugins/{slug}

Additional Information

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