Update VERSION and Changelog for 2.3.1 minor release. (#4121)

* Update VERSION and Changelog for 2.3.1 minor release.

* 2.3.1: update changelog

* Update CHANGELOG.md

reviewer suggestion: add packaging section

Co-authored-by: Be <be.0@gmx.com>

Co-authored-by: Be <be.0@gmx.com>

CHANGELOG.md

@@ -1,6 +1,14 @@
 # Changelog
 
-## [2.3.0](https://launchpad.net/mixxx/+milestone/2.3.0)
+## 2.3.1
+* Echo fix: echo added left channel samples to right channel [#4141](https://github.com/mixxxdj/mixxx/pull/4141)
+* Fix bad phase seek when starting from preroll. [lp1930143](https://bugs.launchpad.net/mixxx/+bug/1930143) [#4093](https://github.com/mixxxdj/mixxx/pull/4093)
+* Fix wrong track being recorded in History [lp1933991](https://bugs.launchpad.net/mixxx/+bug/1933991) [#4041](https://github.com/mixxxdj/mixxx/pull/4041)
+* Rekordbox: Handle exception when parsing corrupt .pdb files [lp1933853](https://bugs.launchpad.net/mixxx/+bug/1933853) [#4040](https://github.com/mixxxdj/mixxx/pull/4040)
+### Packaging
+* Install udev rule file to the correct location automatically in the CMake install step when CMAKE_INSTALL_PREFIX is `/` or `/usr`. It is no longer necessary to manually copy the udev rule file in packaging scripts. [#4126](https://github.com/mixxxdj/mixxx/pull/4126)
+* Various build fixes for FreeBSD [#4122](https://github.com/mixxxdj/mixxx/pull/4122) [#4123](https://github.com/mixxxdj/mixxx/pull/4123) [#4124](https://github.com/mixxxdj/mixxx/pull/4124)
+## [2.3.0](https://launchpad.net/mixxx/+milestone/2.3.0) (2021-06-28)
 ### Hotcues ###
 * Add hotcue colors and custom labels by right clicking hotcue buttons or right clicking hotcues on overview waveforms [#2016](https://github.com/mixxxdj/mixxx/pull/2016) [#2520](https://github.com/mixxxdj/mixxx/pull/2520) [#2238](https://github.com/mixxxdj/mixxx/pull/2238) [#2560](https://github.com/mixxxdj/mixxx/pull/2560) [#2557](https://github.com/mixxxdj/mixxx/pull/2557) [#2362](https://github.com/mixxxdj/mixxx/pull/2362)
 * Mouse hover cues on overview waveform to show time remaining until the cue [#2238](https://github.com/mixxxdj/mixxx/pull/2238)

CMakeLists.txt

@@ -58,7 +58,7 @@ if(NOT CMAKE_CONFIGURATION_TYPES)
   endif()
 endif()
 
-project(mixxx VERSION 2.3.0)
+project(mixxx VERSION 2.3.1)
 # Work around missing version suffixes support https://gitlab.kitware.com/cmake/cmake/-/issues/16716
 set(MIXXX_VERSION_PRERELEASE "") # set to "alpha-pre" "beta" or ""