Update README.md

README.md

@@ -118,6 +118,7 @@ Scheme — NodeRSA supports multiple format schemes for import/export keys:
 
   * `'pkcs1'` — public key starts from `'-----BEGIN RSA PUBLIC KEY-----'` header and private key starts from `'-----BEGIN RSA PRIVATE KEY-----'` header
   * `'pkcs8'` — public key starts from `'-----BEGIN PUBLIC KEY-----'` header and private key starts from `'-----BEGIN PRIVATE KEY-----'` header
+  * `'openssl'` — public key starts from `'ssh-rsa'` header and private key starts from `'-----BEGIN OPENSSH PRIVATE KEY-----'` header
   * `'components'` — use it for import/export key from/to raw components (see example below). For private key, importing data should contain all private key components, for public key: only public exponent (`e`) and modulus (`n`). All components (except `e`) should be Buffer, `e` could be Buffer or just normal Number.     
 
 Key type — can be `'private'` or `'public'`. Default `'private'`<br/>