connect API for Svelte

[djlauk]

(Note: This issue is a follow-up notice to a discussion on another channel.)

Using Rdx with Svelte works quite nicely, when exposed as a custom Svelte store.

In order not to communicate any preference for any UI solution, it seems a logical consequence, to move the existing connect API for web components down from the top level, so a project can import either one. Having each of them in a separate module should provide optimal support for tree shaking when bundling.

• [ ] Provide connect API for Svelte
• [ ] Move connect API for web components (or generally class based components)
• [ ] Update documentation