imagetag: <tag to be used on 'docker build'>
 tags:
   - <YAML array of custom tags to create and push into registry>
 downloadpath: <local root path to download files into>
 s3:
   bucket: <base bucket to download files from>
   basepath: <inside the bucket the root path for files to be downloaded>
 files:
   - s3path: <path to file in S3 after [s3.bucket]/[s3.basepath]>
     filename: <local path + name of the file, will be downloaded into [downloadpath]/[localname]>
     permission: <[optional] file permissions, default 0644>
 commands:
   - <YAML array containing shell commands (currently /bin/bash) to be run before 'docker build'>

 You can use ${<KEY>} as a placeholder in harbor.yml to be replaced by the value passed in a -e flag

Usage:
  harbor -h | --help
  harbor --version
  harbor --list-variables
  harbor [-e KEY=VALUE]... [options]
  harbor [options]

Options:
  -h, --help                    Show this screen.
  -v, --version                 Show version.
  --list-variables              Parses harbor.yml and prints out every ${KEY} found.
  -e KEY=VALUE                  Replaces every ${KEY} in harbor.yml with VALUE
  --debug                       Dry-run and print command executions.
  --no-download                 Prevents downloading files from S3.
  --no-commands                 Prevents commands in harbor.yml from being run.
  --no-docker                   Do not run 'docker build', 'docker tag' and 'docker push' commands.
  --no-docker-push              Do not run 'docker push' after building and tagging images.
  --docker-opts=<DOCKER_OPTS>   Will be appended to the base docker command (ex.: 'docker <docker-opts> command').
  --no-latest-tag               Do not build image tagging as 'latest',
                                will use the first tag in 'tags' list from harbor.yml or
                                generate a timestamped tag if no 'tags' list exists.