Snippet on target and continuum of usages

[emmanuelbernard]

Explain in a couple of paragraphs that Quarkus is offering in the same ecosystem:

• centered on cloud native applications
• platform has a continuum from Function (serverless), to microservices and more classical applications
• continuum of (optional) opinionated happy path (80% usage), smoothly transitioning to vanilla usage of the best of breed frameworks and standards for more powerful usages
• a choice with similar API with Imperative and Reactive approach

[cescoffier]

Fixed in master, in the continuum document.