Automatically generate README.md files

[NimJay]

Background info/Context:

• Each folder containing a set of samples should contain a README.md file (as noted by the samples' requirements here).
• See README.md template here.
• This README.md ensures visitors of this repository know:
  • where the full tutorials/instructions are for a given sample file.
  • what the sample is doing.
• Today, sample authors are expected to manually create these README.md files.

Feature request: Ideally, these README.md would be generated automatically. This would reduce the amount of back-and-forth between sample authors, and reduce the work necessary to create new GKE samples.

Additional info:

• This feature request was inspired by this conversation/pull-request.