Generate type descriptors for TypeScript and Flow

[carragom]

• Platform:
  Linux stretch 4.9.0-2-amd64 Fill out README #1 SMP Debian 4.9.18-1 (2017-03-30) x86_64 GNU/Linux
• Database:
  SQLite3
• Lux Version:
  1.1.7
• Node Version:
  v6.10.2

I think it would be beneficial for Lux users to have TypeScript and Flow type descriptors. In many cases this could be even better than formal documentation. Once the generation of these types is in place, I could probably maintain at least the TS version and document how to properly setup VSCode to use Lux with TS.