TypeScript support

[SemyonMakhaev]

Hi! We'd like to use the component in our TypeScript project.
This adds type definitions to the module

+r @talyssonoc @dudko

[mrkvon]

This would be very useful. The CI-test failed for seemingly unrelated reasons.

/home/travis/.yarn/lib/cli.js:45703
  let {
      ^
SyntaxError: Unexpected token {
    at exports.runInThisContext (vm.js:53:16)
    at Module._compile (module.js:413:25)
    at Object.Module._extensions..js (module.js:452:10)
    at Module.load (module.js:355:32)
    at Function.Module._load (module.js:310:12)
    at Module.require (module.js:365:17)
    at require (module.js:384:17)
    at Object.<anonymous> (/home/travis/.yarn/bin/yarn.js:24:13)
    at Module._compile (module.js:434:26)
    at Object.Module._extensions..js (module.js:452:10)
> Yarn was installed, but doesn't seem to be working :(.

Is it possible to rerun and debug them?