TODO List

Improvement of path matcher
Option for rewriting path like
```
https://example.com:8080/path/to -> http://backend:3030/any_path
```
Currently, incoming path (/path/to/) is always preserved in the mapping process, i.e., mapped to backend:3030/path/to.
Smaller footprint of docker image using musl
Refactoring
Options to serve custom http_error page.
etc.