Change container workflow

Dockerfile workflow:

1. Copy newly created file named "playbook-execute.sh" from repository to "/entrypoint.sh"
2. Change "WORKDIR" to "/playbook-execution".
3. Set this file as entrypoint.

Entrypoint workflow:

1. Copy playbook from mount path ("/playbook") to "/playbook-execution" directory.
2. Change directory to "/playbook-execution".
3. Install roles using ansible-galaxy - assume that ssh-key is set using ssh-agent or mounted under proper directory ("/root/.ssh")
4. Execute ansible-playbook command passing all "entrypoint.sh" parameters to this command.