Bump version number

Author: naavis

CHANGELOG.md

@@ -5,7 +5,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## 2.3.1 - 2019-07-14
 
 ### Fixed
 - Fixed build configuration bug where resources were not being linked on Linux

appveyor.yml

@@ -1,4 +1,4 @@
-version: '2.3.0-{build}'
+version: '2.3.1-{build}'
 branches:
   only:
     - master