Update to angular 11

Bumps up angular version to 11.

v2.0.0: Merge pull request #34 from JNaftali/master

• Rewrote using the angular 9 CLI (dropped angular 8 support)
• moved https://github.com/abhazelton/animate-on-scroll-test into this repo

v1.2.0 Ivy Support

• Adds Angular 9/Ivy support by replacing Renderer with Renderer2

v1.1.0: Updated readme

• Added Angular Universal Support
• Remove need for rxjs-compat