Add Typescript definitions

[Robin Modisch]

Seems like type definitions are missing, which makes integration with a typescript (svelte) project cumbersome:

Hint: Could not find a declaration file for module 'handtrackjs'. '/handtrackjs/src/index.js' implicitly has an 'any' type.
  Try `npm i --save-dev @types/handtrackjs` if it exists or add a new declaration (.d.ts) file containing `declare module 'handtrackjs';` (ts)

[Matt Kingsbury]

Have the developers made any progress on this? I am encountering the same issue while developing a React application.