Replace Angular 2/4 link with example

[KhaledSMQ]

Description:

Remove the link Angular 2/4 Version this repository created to solve NgZone events problem. and now as i mention in #524 with example https://stackblitz.com/edit/angular-ngformbuilder you can use formBuilder without third part directly with angular.

If you would like i can create separate example repository using angular 7.

[kevinchappell]

@KhaledSMQ That would be great! Then we can update the docs with the Angular 7 demo as well.

[harshalyelpale]

@KhaledSMQ @kevinchappell It is working perfectly with Angular 8.0. That's excellent!!. Thank you, both of you :). How do we get JSON Schema (form schema) in Angular Controller(so that we can save into database and load the later), after a click on the Save button?

Actually, I'm working on a project where the end-user can dynamically define a form/template (heading, text boxes, radio buttons, etc). Once the form/templates are defined, other users may load the form/templates (HTML form) and enter data into it and submit to the database.