JS / TS Scaffolding

[guybedford]

As also discussed at CTW, The ComponentizeJS has a need for code scaffolding of the JavaScript / TypeScript code for a given interface. @eduardomourar suggested that if we had such code for TypeScript generation it would effectively form a type generation itself as well. Working on a bindgen for this kind of case seems like it would be beneficial and belongs here rather than in ComponentizeJS itself. This also seems to have some crossover with the work of @dbaeumer.