[feature] TypeScript support

[apsdehal]

Motivation and Context

TypeScript enables type checking for JavaScript and will help improve quality of code on JS side.
This PR enables typescript compilation support and makes it work alongside ES6.

How Has This Been Tested

Same commands nothing has changed. A separate PR will be opened for moving files to .ts.

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have completed my CLA (see CONTRIBUTING)
• I have added tests to cover my changes.
• All new and existing tests passed.

[codecov-io]

Codecov Report

Merging #411 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #411   +/-   ##
=======================================
  Coverage   56.74%   56.74%           
=======================================
  Files         175      175           
  Lines        8094     8094           
  Branches       84       84           
=======================================
  Hits         4593     4593           
  Misses       3501     3501

Flag	Coverage Δ
#CPP	52.35% <ø> (ø)	⬆️
#JavaScript	10% <ø> (ø)	⬆️
#Python	78.82% <ø> (ø)	⬆️

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