Added -t target parameter and its description to README

[halilkaya]

Updated -h output on README and added -t TARGET parameter to see by reading the README easily.

[konstruktoid]

I don't believe there is an -t option?
https://github.com/docker/docker-bench-security/blob/master/docker-bench-security.sh#L51-L57

[halilkaya]

Weird. Therefore, the current docker/docker-bench-security:latest image in the registry is different than the codebase. When I pull latest and run -h, the output is:

  usage: docker-bench-security.sh [options]

  -b           optional  Do not print colors
  -h           optional  Print this help message
  -l FILE      optional  Log output in FILE
  -c CHECK     optional  Comma delimited list of specific check(s)
  -e CHECK     optional  Comma delimited list of specific check(s) to exclude
  -i INCLUDE   optional  Comma delimited list of patterns within a container name to check
  -x EXCLUDE   optional  Comma delimited list of patterns within a container name to exclude from check
  -t TARGET    optional  Comma delimited list of images name to check

[konstruktoid]

You're correct @halilkaya. The Docker image is out-of-date, please have a look at #405

[halilkaya]

Oh, sorry. This parameter is removed 11 months ago.

ef206be

OK, then. I'm closing the PR and waiting for the new release. :)

Thanks, @konstruktoid