Auto-generate command instructions for README.md

[ace-n]

Once all our samples are converted to use yargs (or some other arg-parsing library that auto-generates command-line usage instructions), we should consider having a script insert those instructions into our Markdown documentation automatically (instead of manually cutting-and-pasting things).

Thoughts?

[jmdobry]

Things the script needs to know, per product:

• Product name
• Product description
• Setup section
  • Link to any general prerequisites and general "how to run a sample" instructions
  • Extra steps, either defined directly in metadata, or metadata points to a markdown file to be included
• Samples section
  • Title of sample
  • Links to where it's used in the documentation
  • Links to source code
  • Instructions on how to run it
    • Defined instructions in metadata
    • Specify markdown to be included
    • Specify command to be executed, using the resulting stdout as the instructions

Put metadata in .samples.json file in sample directory. To generate README in that directory, run the script in that directory.

[jmdobry]

Done.