Updates for all angular.io links to the new angular.dev domain. Additionally, adjustment to new resources where the equivalent does not exist on the new site (e.g. Tour of Heroes tutorial)
The use of the custom path functions from `@angular-devkit/core` have been
removed in favor of the built-in functions from Node.js. These provide
equivalent functionality with an improvement in performance. The amount
of custom code executed has also been reduced.
