Add WebComponent connector

[Kikobeats]

After some conversations could be interesting create a Web Component version of the current (and the main) React connector.

Why

• The implementation will be very similar to the current react connector since web component and react API are very similar ([vanilla] affordable interface as web component #140).
• It can replace the current vanilla version and the build size will be smaller since the current vanilla version is based on the react version and it needs to include react and reac-dom as part of the bundle ([vanilla] reduce bundle size #137).
• One of the big Web Components caveats is browser support. Although nowadays it's not too good, eventually it could be better in the future and polyfills will serve on demand based on user agent using polyfill.io.

(non exhaustive list, feel free the comment)

Since I never wrote a Web Component before, I don't know if I need to consider any more caveats.

[Kikobeats]

Nice to have but it isn't a thing is going to happen in the short term