* Fix documentation to make `yarn test` work out of the box

Before, invoking `yarn test` croaked on a missing src/component-index.js
file. In another part of the README, the missing instruction to generate
this file was found.

* Fix CI: Unauthenticated git protocol on port 9418 is no longer supported

GitHub is deprecating the service which answered unauthenticated git
protocol requests. Either it happened already, or they are running
brownouts.

* This is where I meant to leave that comment

Co-authored-by: Andreas Motl <andreas.motl@panodata.org>