make form for entering publication data

[sujato]

Currently data is entered in publication.json by hand, which is hard, slow, and error-prone.

Let's use a form instead! Here's a JSON-form based on modern standards.

https://github.com/mistio/mist-form

[ccronje]

This would be helpful Bhante. Translators could be prompted to complete the form the first time they select Publish in Bilara.