chore: add several badges (#24)

Signed-off-by: tison <[email protected]>

README.md

@@ -1,5 +1,19 @@
 # Logforth Project
 
+[![Crates.io][crates-badge]][crates-url]
+[![Documentation][docs-badge]][docs-url]
+[![Apache 2.0 licensed][license-badge]][license-url]
+[![Build Status][actions-badge]][actions-url]
+
+[crates-badge]: https://img.shields.io/crates/v/logforth.svg
+[crates-url]: https://crates.io/crates/logforth
+[docs-badge]: https://docs.rs/logforth/badge.svg
+[docs-url]: https://docs.rs/logforth
+[license-badge]: https://img.shields.io/crates/l/logforth
+[license-url]: LICENSE
+[actions-badge]: https://github.com/tisonkun/logforth/workflows/CI/badge.svg
+[actions-url]:https://github.com/tisonkun/logforth/actions?query=workflow%3ACI
+
 A versatile and extensible logging implementation.
 
 The name comes from an antonym to the [Logback](https://logback.qos.ch/) project.