added possiblity to build jar file and override shutdown behavior when closing via alt-f4 or the close button of the window

Projekte/mdga/client/build.gradle

@@ -26,3 +26,14 @@ implementation project(":mdga:model")
     mainClass = 'pp.mdga.client.MdgaApp'
     applicationName = 'MDGA'
 }
+
+tasks.register('fatJar', Jar) {
+    duplicatesStrategy = DuplicatesStrategy.EXCLUDE
+    manifest {
+        attributes 'Main-Class': 'pp.mdga.client.MdgaApp'
+    }
+    from {
+        configurations.runtimeClasspath.collect { it.isDirectory() ? it : zipTree(it) }
+    }
+    with jar
+}