feat(build): upgrade to v6

[Toxicable]

Includes the minimal changes required to upgrade to v6.

Don't merge till v6 final - will be updated at that point.

[peterbakonyi05]

I know it is not final, just in case someone else tries to update based on this PR like I did. When running npm i and then npm start:

** Angular Live Development Server is listening on localhost: 4200, open your browser on http://localhost:4200/ **
 13% building modules 31/35 modules 4 active …\@nguniversal\common\esm5\common.es5.js✖ ｢wdm｣: Error: No module factory available for dependency type: ContextElementDependency
    at addDependency (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:406:12)
    at iterationOfArrayCallback (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:88:3)
    at addDependenciesBlock (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:422:5)
    at iterationOfArrayCallback (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:88:3)
    at addDependenciesBlock (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:425:5)
    at Compilation.processModuleDependencies (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:433:4)
    at afterBuild (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:560:16)
    at _this.buildModule.err (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:606:11)
    at callback (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:357:35)
    at module.build.error (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:393:12)
    at resolveDependencies (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\ContextModule.js:219:4)
    at ContextModule.result.resolveDependencies (C:\Github\universal-starter\node_modules\@ngtools\webpack\src\angular_compiler_plugin.js:475:25)
    at ContextModule.build (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\ContextModule.js:148:8)
    at Compilation.buildModule (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:361:10)
    at factory.create (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\Compilation.js:587:15)
    at hooks.afterResolve.callAsync (C:\Github\universal-starter\node_modules\@angular-devkit\build-angular\node_modules\webpack\lib\ContextModuleFactory.js:150:16)
C:\Github\universal-starter\node_modules\neo-async\async.js:14
    throw new Error('Callback was already called.');
    ^

Error: Callback was already called.

I think the problem is that webpack ^4.5.0 should be removed from package.json because it will install webpack twice (4.6.0 in the root and 4.5.0 in node_modules/@angular-devkit/build-angular), which is the root cause of this problem

[Toxicable]

@peterbakonyi05 It works fine for me, however I am using yarn instead, could you give that a shot?

[peterbakonyi05]

@Toxicable Finnaly had some time to check. If I install using yarn it works fine. When running npm ls webpack after yarn install:

$ npm ls webpack
[email protected] C:\Github\universal-starter
+-- @angular-devkit/[email protected]
| `-- [email protected]  deduped
`-- [email protected]