[RFC] improve lerna monorepo setup

[raymondfeng]

The draft contains the following changes:

1. Upgrade dependencies to latest versions
2. Tidy up package.json for consistencies
3. Introduce project references for TypeScript to allow top-down and incremental builds
4. Add prettier formatting
5. Switch from tslint to eslint
6. Add license/copyright headers to all ts/js files (I have a tool to automate it)

TODOs:

1. Add nyc test coverage
2. Add travis CI integration (just realized it's already using github CI)
3. Consider husky for conventional commits
4. Automate apidocs generation using Microsoft api-extractor/api-documenter
5. Enforce DCO (Signed-off-by)