This PR moves the puppeteer source code into separate mono-repo packages:
- `puppeteer` and `puppeteer-core` are now separated into their own
packages.
- `puppeteer-core` has a new exports called `puppeteer-core/internal`
for internal usage.
Tests and various tools have been updated to accommodate the migration.
* chore: implement a test runner on top of mocha
This PR implements a test runner on top of mocha
that performs multiple mocha runs as defined in
TestSuites.json and compares the outcome of the runs
against TestExpectations.json. This allows us to
remove most of helpers from mocha-utils and be more
flexible when defining the test configurations.