Pre-release changes (#301)

* Pre-release changes

* Removed Qt5 from `README.md`

* Edited ChangeLog

CHANGELOG

@@ -1,3 +1,10 @@
+libqtxdg-4.0.0 / 2024-04-17
+============================
+ * Ported to Qt6.
+ * Consider the EV `XDG_CURRENT_DESKTOP` as a colon-separated list.
+ * Fixed an FTBFS with `BUILD_DEV_UTILS` enabled.
+ * Fixed a test file after recent changes in Qt6.
+
 libqtxdg-3.12.0 / 2023-11-05
 ============================
  * Fixed a typo and bumped the version.

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.16.0 FATAL_ERROR)
+cmake_minimum_required(VERSION 3.18.0 FATAL_ERROR)
 # CMP0000: Call the cmake_minimum_required() command at the beginning of the top-level
 # CMakeLists.txt file even before calling the project() command.
 # The cmake_minimum_required(VERSION) command implicitly invokes the cmake_policy(VERSION)

README.md

@@ -2,17 +2,17 @@
 
 ## Overview
 
-`libqtxdg` is a Qt 5 implementation of freedesktop.org XDG specifications.   
+`libqtxdg` is a Qt implementation of freedesktop.org XDG specifications.  
 
-It is maintained by the LXQt project and nearly all LXQt components are depending on it. Yet it can be used independently from this desktop environment, too.   
+It is maintained by the LXQt project and nearly all LXQt components are depending on it. Yet it can be used independently from this desktop environment, too.  
 
-The library is able to use GTK+ icon theme caches for faster icon lookup. The cache file can be generated with utility `gtk-update-icon-cache` on a theme directory. If the cache is not present, corrupted, or outdated, the normal slow lookup is still run.   
+The library is able to use GTK+ icon theme caches for faster icon lookup. The cache file can be generated with utility `gtk-update-icon-cache` on a theme directory. If the cache is not present, corrupted, or outdated, the normal slow lookup is still run.  
 
 ## Installation
 
 ### Sources
 
-At runtime qtbase is needed. gtk-update-icon-cache represents an optional runtime dependency for the reasons stated above.   
+At runtime qtbase is needed. gtk-update-icon-cache represents an optional runtime dependency for the reasons stated above.  
 Additional build dependencies are CMake, qtsvg, qttools, [lxqt-build-tools](https://github.com/lxqt/lxqt-build-tools) and optionally Git to pull latest VCS checkouts.
 
 The code configuration is handled by CMake so all corresponding generic instructions apply. Specific CMake variables are
@@ -23,6 +23,6 @@ To build and install run `make` and `make install`respectively.
 
 ### Binary packages
 
-The library is provided by all major Linux distributions like Arch Linux, Debian, Fedora and openSUSE.   
+The library is provided by all major Linux distributions like Arch Linux, Debian, Fedora and openSUSE.  
 Just use the distributions' package managers to search for string `libqtxdg`.