feat: adds plugin feature for extending cli with new commands

[rmauge]

Updates the CLI to allow adding new commands.

New commands are discovered simply by being present on the path. This implementation is similar to other cli tools that support plugins: any executable that is found on the path that is named “ask-” is considered a plugin. Guard rails are in place to ensure that a plugin cannot override an internal command. Plugins with the same names are also detected and a warning given to the user. 

You can test the feature with a sample plugin. This plugin can generate a new Intent and handler on a skill created with "ask new".

Install the beta CLI  based on ask-cli 2.27.0:
npm install git+https://github.com/rmauge/ask-cli.git\#plugin-feature-qa -g

The executable "ask_plugin" should now available to be used as a drop-in replacement for "ask".

Install a sample plugin for generating skill artifacts:
npm install git+https://github.com/rmauge/ask-generate.git -g

The ask-generate command should now be available. Verify by running "ask_plugin" and look for the "generate" command.

Generate a new Intent:
Navigate to a new skill that follows the same layout as created by "ask new".
ask_plugin generate intent StartOrder "begin my order" "place Order" "start order" "new order"

Your skill IM model should now have a new Intent added and a new Handler under lambda/handlers.

To uninstall:
npm uninstall --location=global ask-cli-plugin
npm uninstall --location=global ask-generate

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[CamdenFoucht]

Hi @rmauge, thank you for the pull request! We will try to review it soon 👍