update README.md

README.md

@@ -44,10 +44,19 @@ authenticator.verifyToken(formattedKey, '000 000');
 
 ### API
 
-* `generateKey()` generates a 32-character (160-bit) base32 key
-* `generateToken(formattedKey)` generates a 6-digit (20-bit) decimal time-based token
-* `verifyToken(formattedKey, formattedToken)` validates a time-based token within a +/- 30 second (90 seconds) window
-  * returns `null` on failure or an object such as `{ delta: 0 }` on success
+### `generateKey()`
+
+generates a 32-character (160-bit) base32 key
+
+### `generateToken(formattedKey)`
+
+generates a 6-digit (20-bit) decimal time-based token
+
+### `verifyToken(formattedKey, formattedToken)`
+
+validates a time-based token within a +/- 30 second (90 seconds) window
+
+returns `null` on failure or an object such as `{ delta: 0 }` on success
 
 QR Code
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