Adds sourcemap and minification to javascript added via the `scripts` array in `.angular-cli.json`.
`script-loader` is no longer used, which should help with CSP since it used `eval`.
Scripts will no longer appear in the console output for `ng build`, as they are now assets instead of webpack entry points.
It's no longer possible to have the `output` property of both a `scripts` and a `styles` entry pointing to the same file. This wasn't officially supported or listed in the docs, but used to be possible.
Fix#2796Fix#7226Fix#7290
Related to #6872
Adds the flag 'serviceWorker' to angular-cli.json that enables support for @angular/service-worker.
When this flag is true, production builds will be set up with a service worker. A ngsw-manifest.json file
will be generated (or augmented) in the dist/ root, and the service worker script will be copied there.
A short script will be added to index.html to register the service worker.
@angular/service-worker is a dependency of @angular/cli, but not of generated projects. It is desirable
for users to be able to update the version of @angular/service-worker used in their apps independently
of the CLI version. Thus, the CLI will error if serviceWorker=true but @angular/service-worker is not
installed in the application's node_modules, as it pulls all the service worker scripts from there.
If the flag is false the effect on the CLI is minimal - the webpack plugins associated with the SW are
not even require()'d.
Closes#4544
