Add Blueprint File for User Previews in Plugin

[askcode21]

Your plugin does not yet have a blueprint file for user previews. If you'd like to enable previews, please follow these steps to create a blueprint.

1. Test your plugin in Playground
2. Fix any bugs in your plugin that prevent it from working in Playground.
3. Download blueprint.json
4. Commit your blueprint to svn.

More info can be found in the plugin handbook.

https://paste.pics/QL4IT