Feature: Add template which would support WordPress single block directory

[gziolo]

There is this question from @bph:

If I wanted to use it for a single block plugin, and I see a great use case for it, but it would need boilerplate pluginname.php. I created the file added the header information and move the index.php information to that file. That was easy, so easy, that it might go into the script?

I think we should either add a template that addresses the needs of the single block directory project. An alternative approach would be to add more optional prompts that cover all metadata required by the WordPress plugin.