Felt: On-demand ES6/CSS Bundler

Felt is an on-demand bundler designed for modern JavaScript (ES6 and beyond, typically transpiled via Buble/Rollup) and CSS (CSS Next), serving primarily as a development middleware or a static asset exporter. Currently at version 0.3.2, it requires Node.js 6 or above to run. The package offers three main modes of operation: a standalone CLI web server for quick local development, an Express.js middleware for integration into existing Node.js applications, and a static file exporter for pre-compiling assets for deployment. Its core functionality is highly extensible through 'recipes' and a plugin architecture, exemplified by modules like `felt-rollup`, which allows developers to define custom handler logic for different file types. This on-demand compilation approach is a key differentiator, focusing on speed during development rather than exhaustive pre-bundling.