Preparing 2.4.0 release

Modules/Media/changelog.yml

 url: https://github.com/AsgardCms/Platform
 versions:
-    "2.4.0@unreleased":
+    "2.4.0":
         added:
             - new blade directive for thumbnails <code>@thumbnail('path', 'thumbnailName')</code>
         changed:

Modules/User/changelog.yml

 url: https://github.com/AsgardCms/Platform
 versions:
-    "2.4.0@unreleased":
+    "2.4.0":
         added:
             - Trigger an event (<code>UserIsCreating</code>) before a user is created, allowing customising its data via listeners
         changed:

Modules/Workshop/changelog.yml

 url: https://github.com/AsgardCms/Platform
 versions:
-    "2.4.0@unreleased":
+    "2.4.0":
         added:
             - Add the ability to set custom stubs folder used by generated modules
     "2.0.0":

Themes/Adminlte/changelog.yml

 url: https://github.com/AsgardCms/Platform
 versions:
-    "2.4.0@unreleased":
+    "2.4.0":
         changed:
             - Moved to using laravel.mix
             - Dependencies are now handled by NPM instead of Bower

Themes/Flatly/changelog.yml

 url: https://github.com/AsgardCms/Platform
 versions:
-    "2.4.0@unreleased":
+    "2.4.0":
         added:
             - Moved to using laravel.mix
     "2.0.0":

composer.json

@@ -8,7 +8,7 @@
         "laravel",
         "laravel5"
     ],
-    "version": "2.3.0",
+    "version": "2.4.0",
     "license": "MIT",
     "type": "project",
     "require": {