tsconfig monorepo tricks like config inheritance & a composite config with references to other packages

[matheus23]

By @dholms in #82:

I briefly tried to do some tsconfig monorepo tricks like config inheritance & a composite config with references to other packages. But the current build setup was preventing me from doing that. Namely, copying the tsconfig into the dist folder which would add an extra director to the file hierarchy & screw up relative paths. I think this should be doable, but we may need to chat through the current build process. & maybe belongs in a future PR?