Update changelog

Signed-off-by: Denis Varlakov <denis@dfns.co>

Author: survived

CHANGELOG.md

@@ -1,12 +1,15 @@
 # hd-wallet crate changelog
 
 ## v0.6.0
-* Remove slip10-like derivation that can be instantiated with any curve: it is very inefficient
+* BREAKING: Remove slip10-like derivation that can be instantiated with any curve: it is very inefficient
   when instantiated with certain curves, and may also enable attacker to perform DoS attack by
   finding derivation path that results into very long computation [#14]
 * Add stark-specific derivation: secure and efficient derivation for stark curve [#14]
+* Use `Error` trait from `core` instead of `std` [#15]
+  * BREAKING: remove `std` feature as the lib is fully no_std now
 
 [#14]: https://github.com/LFDT-Lockness/hd-wallet/pull/14
+[#15]: https://github.com/LFDT-Lockness/hd-wallet/pull/15
 
 ## v0.5.1
 * Update docs and repo link [#11]