Create README.md and make lib.rs tfn into doc test

Author: valentinegb

README.md

@@ -0,0 +1,28 @@
+# `beat_saber_map`
+
+[![Crates.io Version](https://img.shields.io/crates/v/beat_saber_map)](https://crates.io/crates/beat_saber_map)
+[![docs.rs](https://img.shields.io/docsrs/beat_saber_map)](https://docs.rs/beat_saber_map)
+[![Rust](https://github.com/valentinegb/beat-saber-map-rs/actions/workflows/rust.yml/badge.svg)](https://github.com/valentinegb/beat-saber-map-rs/actions/workflows/rust.yml)
+
+Read and write Beat Saber maps with Rust.
+
+```rs
+use beat_saber_map::BeatSaberMap;
+
+let map = BeatSaberMap::from_dir("sample").unwrap();
+
+assert_eq!(map.info.song.title, "Magic");
+```
+
+Documentation can be found on [docs.rs](https://docs.rs/beat_saber_map).
+
+## Roadmap
+
+- [ ] Create structures for map files
+  - [x] [`Info`](https://docs.rs/beat_saber_map/latest/beat_saber_map/info/struct.Info.html)
+  - [ ] `Audio`
+  - [ ] `Beatmap`
+  - [ ] `Lightshow`
+- [ ] Create utility methods for map file structures and [`BeatSaberMap`](https://docs.rs/beat_saber_map/latest/beat_saber_map/struct.BeatSaberMap.html)
+  - [x] [`BeatSaberMap::from_dir()`](https://docs.rs/beat_saber_map/latest/beat_saber_map/struct.BeatSaberMap.html#method.from_dir)
+  - [ ] More...

src/lib.rs

@@ -1,5 +1,13 @@
 //! Read and write Beat Saber maps with Rust.
 //!
+//! ```
+//! use beat_saber_map::BeatSaberMap;
+//!
+//! let map = BeatSaberMap::from_dir("sample").unwrap();
+//!
+//! assert_eq!(map.info.song.title, "Magic");
+//! ```
+//!
 //! Refer to the [BSMG Wiki](https://bsmg.wiki/mapping/map-format.html) for language-agnostic documentation.
 
 #![warn(missing_docs)]
@@ -43,13 +51,3 @@ impl BeatSaberMap {
         })
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn from_dir_doesnt_fail() {
-        BeatSaberMap::from_dir("sample").unwrap();
-    }
-}