Similar to what cockpit-composer does. This is rather simplistic, but
does fine until we need more complex scenarios.
Also use plain shell in test/run, there are no bashisms.
Closes#291
Rename some files and change some identifiers to be neutral to the
application name. This makes it simpler to change everything to a proper
name when cloning this project.
Document in the README how to find the remaining places to change.
Closes#20