Pug support

[dLiubchenko]

Hello, as you know Jade is deprecated and it became Pug. After migration form jade to pug, we are faced with a problem, such as interpolation, that worked in Jade, but not in Pug.
Is it old runtime.js in slug json still compatible for pug? (by the way all links to runtime.js file in Spine official docs is already 404)