Add `create-dash-docset.js` to create dash docset from phaser.json

[DanEEStar]

This added script will generate a docset for Dash and other compatible tools.

The Dash docset contains a simple sqlite-database. I have seen that most of the needed data is already in the phaser.json file and I could create this script similary to the existing jsdoc-to-sqlite.js script.

I have seen Pull-Requests #97 and #129 which have a similiar goal in creating a Dash docset. But I think with the approach in this script and the provided metadata in phaser.json the docset will be better than with parsing the existing html-files like in the other pull requests.