Add release notes for Splinter 0.5.24
# Release Notes
+## Changes in Splinter 0.5.24
+
+### libsplinter
+
+* Verify proposal circuit version is supported for vote. Verify that the circuit
+ version for the proposal that is being voted on is still valid for the
+ currently support circuit versions.
+
+### splinter CLI
+
+* Create Database file with 640 permissions.
+
+* Add receipt store to the `splinter upgrade` CLI command.
+
+* Check that the value given for the `--rest-api-endpoint` splinterd CLI option
+ contains 'http://' or 'https://' and exit with an error if it does not.
+
+### scabbard
+
+* Detect incorrect state daemon. Changes the `ScabbardFactory` builder to fail
+ if LMDB state is not enabled, but there are any existing LMDB files in the
+ state directory.
+
## Changes in Splinter 0.5.23
### Highlights
