Fix options

[feloy]

Options with single letter and double dash (--f, --i, --o) are not common. This PR changes to have a long name (file, image, output) with double dash and single letter with single-dash:

./bin/doa analyze --help
Analyze the Dockerfile and discover potential issues when deploying it on OpenShift. It accepts the project root path or the Dockerfile path.

Usage:
  doa analyze [flags]

Examples:
  doa analyze -f /your/local/project/path[/Dockerfile_name]

Flags:
  -f, --file string     Container file to analyze
  -h, --help            help for analyze
  -i, --image string    Image name to analyze
  -o, --output string   Specify output format, supported format: json

• Small fix on doc with wrong expose port

[jeffmaury]

@feloy please rebase

[jeffmaury]

LGTM