Update documentation

[emyann]

• add Unpkg and JSDelivr links in README.md
• Split simple examples from advanced ones
• Add doc for complex object creation in schema

[TAnas0]

I'll just make a quick note in here that some links are broken in the documentation, especially for the detailed API reference.
Clicking on Registry API reference documentation from the README redirects to: https://morphism.now.sh/classes/morphism.morphismregistry
I believe it should be: https://morphism.now.sh/classes/_morphismregistry_.morphismregistry

[emyann]

Ah thank you a lot @TAnas0 for the heads up! I'll update the readme accordingly!

[drielnox]

@emyann It's possible add some examples of how to use the Registry API?