Removed InstallKernelCommand

Closes #167 

This is also a requirement for https://github.com/sulu-cmf/sulu-standard/pull/130

__Tasks:__

- [ ] gather feedback for my changes

__Informations:__

| Q             | A
| ------------- | ---
| Tests pass?   | YES
| Fixed tickets | #167 
| BC Breaks     | YES
| Doc           | 
But it means that we should either first merge https://github.com/sulu-cmf/sulu-standard/pull/130 or make another PR on sulu-standard to remove the call to the ScriptHandler