v2 CLI (Alpha)

[paganotoni]

This PR changes the approach we've been taking on the CLI aiming to provide the ability to plugin custom commands to the Buffalo CLI, at a higher level this would compact the stack that will be supported by the Buffalo team and allow Buffalo developers to write plugins that solve their workflow specific needs.

In terms of the ability to override the CLI there are 2 main needs:

• Allowing to add plugins on a Buffalo codebase
• Allowing the use of custom plugins to generate Buffalo applications

These two capacities are vital to improving the out-of-the-box experience for Buffalo by allowing developers to provide support for their own tools and let the Buffalo maintainers focus on a better experience for the frontend stack.

Also, Some of the resulting effects of this new shape of the Buffalo CLI are:

Reducing third-party dependencies (using more of the standard lib)

• Cleaning up old issues
• Improving the maintainability of the Buffalo CLI.

In order to achieve those 2 overall goals we should complete the following steps:

• [x] replace help instructions
• [x] convert base commands to plugins
• [x] rewrite pop plugin
• [x] add plugins command (to list plugins)
• [x] implement plugin override API (remove, add, clear)
• [x] implement custom CLI main feature (in cmd/buffalo)
• [x] implement global per-user default plugins (in $HOME/.buffalo/cmd).

[github-actions[bot]]

This PR is stale because it has been open 45 days with no activity. Remove stale label or comment. Otherwise, this will be closed in 7 days.

[paganotoni]

After some time thinking about this, some conversations with @sio4 (thanks!) and a lot of effort I've decided to close this PR as the amount of effort to get this done may be something we better spend on improving the DX of the framework through other optimizations and not redoing the CLI.