I found that VS Code was taking an age to bring up the intellisense
for TypeScript source files in the `aio/src` folder.
I believe that this is because it was trying to parse all the files in
the `aio/content/examples` folder as well, which is not relevant to the
web app development.
This change restricts the root `aio/tsconfig.json` to only the entry points
for the app, the unit tests and e2e tests.
Igor Minar
Pete Bacon Darwin
Georgios Kalpakas