Jenkins CLI for the init command

Sample output:

bin/gitlab-jenkinsfile-runner init --out ./test-out/ --agent-type docker --runner-version 1.0-beta-11 --jenkins-home /Users/marius/Workspace/sandbox/jenkins-config/home/ --jenkins-war /Users/marius/Workspace/sandbox/jenkins-config/share/jenkins/jenkins.war

Running init with --runner-version=1.0-beta-11 --jenkins-home=/Users/marius/Workspace/sandbox/jenkins-config/home/ --jenkins-war=/Users/marius/Workspace/sandbox/jenkins-config/share/jenkins/jenkins.war --agent-type=docker --out=./test-out/

Please inspect the .dockerignore file to add/remove necessary files for your installation.
The following files are currently removed:

**/*.log
jenkins_home/jobs
jenkins_home/logs

**/*.key
**/*.key.enc
jenkins_home/secrets
jenkins_home/userContent
jenkins_home/users