This is useful when you don't want the server to rebuild in the middle of something.
A good example is when running e2e tests. Especially on larger suites, one would prefer to continue working while the build is tested without compromising tests.
This will break tests on #4744. They should be adjusted to add the `--watch` flag since they depend on the live reload behaviour during `ng e2e`.
Uses existing Protractor API to run it directly instead of using `npm run
e2e`.
Also adds support for the following flags: `--serve`, `--config`,
`--specs`, `--element-explorer`, `--webdriver-update`.
Fix#4256Fix#4478
BREAKING CHANGE: `ng e2e` no longer needs `ng serve` to be running.