doc: update readme

README.md

@@ -49,4 +49,30 @@ let hash = hex::encode(hash_bytes); // String
 assert_eq!(hash, "21bd12dc183f740ee76f27b78eb39c8ad972a757".to_string())
 ```
 
+#### Json Web Token
+
+Add `jwt` features (is enabled by default)
+
+```toml
+[dependencies]
+crypto-utils = { version = "...", features = ["jwt"] }
+```
+
+Create and decode a token
+
+```rust
+use crypto_utils::jsonwebtoken::{Claims, Token};
+
+let user_id = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx";
+
+// create claims
+let claims = Claims::new(user_id, 24);
+
+// create token
+let token = Token::new(secret, claims).unwrap();
+
+// decode token
+let decoded = Token::decode(secret, token.encoded).unwrap();
+```
+
 License: MIT