readme update

README.md

@@ -5,8 +5,8 @@ This is work in progress and does not yet work...
 [![GoDoc](https://godoc.org/github.com/jcmturner/gokrb5?status.svg)](https://godoc.org/github.com/jcmturner/gokrb5)
 
 
-# References
-## RFCs
+## References
+### RFCs
 * RFC 4120 The Kerberos Network Authentication Service (V5)
 [text](https://www.ietf.org/rfc/rfc4120.txt) [html](https://tools.ietf.org/html/rfc4120)
 * RFC 3961 Encryption and Checksum Specifications for Kerberos 5
@@ -14,7 +14,7 @@ This is work in progress and does not yet work...
 * RFC 3962 Advanced Encryption Standard (AES) Encryption for Kerberos 5
 [text](https://www.ietf.org/rfc/rfc3962.txt) [html](https://tools.ietf.org/html/rfc3962)
 
-## Useful Links
+### Useful Links
 * https://en.wikipedia.org/wiki/Ciphertext_stealing#CBC_ciphertext_stealing
 
 ## Thanks