* Enable multiple repositories
* Improve readability
* Adapt documentation
* rerun generator
* Add initial info line
* Improve logging
* Enable configuration in GENERAL section
* Adapt yml abapEnvironmentPullGitRepo
* Add aliases for crendetialsId
* Change order of credentialsId aliases
* Change prio of different names of credentialsId
* Add docu to sidebar
Do not exit with os.Exit(1) but using log.Entry().Fatal() instead
* Golang: forward error details
* extend groovy wrapper to provide proper error message
* create closure for error handling
* Golang step metadata: Config aliases for steps
This will ease following scenarios:
* config migration due to step name changes
* re-use of more general config, e.g. `mavenExecute` in `mavenBuild`
* fix CodeClimate finding
* Fix panic if original stage config does not exist yet
