v0.3.0

In this release, most of the crate was rewritten to be more flexible and allow wildcard embeds.
You probably can best learn the API completely anew. Here are just some changes:

• Assets are configured at runtime via Builder now, not inside the macro.
• Rename assets! to embed!
• You only have to mention files in proc macro that you actually need to embed. You can specify additional ones later.
• Remove template feature: use "modifier" for that, which gives you more control, not having to use reinda's (old) weird template syntax.
• Add print_stats to show information about embedded files at compile time
• Rename debug-is-prod feature to always-prod
• Switch from flate2 to brotli for compression.
• Remove ability to include assets in other assets.
• Internal: remove reinda-core crate