Add Release Notes for 0.5.4
# Release Notes
+## Changes in Splinter 0.5.4
+
+### Highlights
+
+* Includes a number of minor improvements to mesh stability.
+
+* Adds experimental support for including a public key in circuit nodes.
+
+### libsplinter
+
+* Add an optional public key to both ProposedNode and CircuitNode. This public
+ key will be used during challenge authorization. This requires that the
+ Circuit member list is updated to contain CircuitNodes instead of just the
+ node id. This will allow storing the public key directly in the circuit. This
+ is a breaking change against the YAML format, as such if a node is using the
+ YamlAdminServiceStore it cannot support including public keys in the member
+ list and thus will not be able to support challenge authorization.
+
+* Fix a bug that was causing the gameroom example to fail because the Websocket
+ event from Scabbard when a contract was submitted was too large. This was
+ fixed reverting to use json::to_string instead of json::to_string_pretty
+
+* Remove all mesh connection registrations on shutdown
+
+* Remove lock contention when adding connections to mesh
+
+* Change mesh control channel registration from level to edge, in order to
+ process all control messages on a single event firing.
+
+* Replace inproc connection internals with channels, greatly simplifying the
+ implementation.
+
+* Add simple circuit generation via CircuitBuilder and
+ ScabbardCircuitBuilderVeil for creating and testing various configurations of
+ Scabbard circuits. Available through the experimental feature "node".
+
+
## Changes in Splinter 0.5.3
### Highlights
