PoC: React as Template Renderer

[JensRavens]

This story is about trying to integrate react/tsx as a template language into Rails. This is a proof of concept, to be extracted into a gem later on to be used across projects.

Acceptance Criteria

• there's a way to mark templates as .html.tsx (similar to .html.slim) which will render the template
• this should be performant in production and convenient in development
• templates should not allow erb, all dependencies have to be passed via props
• find a way to pass props in a typesafe way to the template
• find a way to deal with translations