De-hardcode the main class name.

src/io/cubyz/dependency/DependencyManager.java

@@ -77,9 +77,18 @@ public static ArrayList<String> fetchDependencies(String pomURL, String absolute
 		} catch(Exception e) {
 			e.printStackTrace();
 		}
-		root = null;
 		return paths;
 	}
+
+	public static String findMainClass() {
+		MyNode plugins = root.get("project").get("build").get("plugins");
+		for(MyNode plugin : plugins.childs) {
+			if(plugin.get("artifactId").value.equals("maven-jar-plugin")) {
+				return plugin.get("configuration").get("archive").get("manifest").get("mainClass").value;
+			}
+		}
+		return "io.cubyz.client.GameLauncher";
+	}
 
 	private static void downloadDependencies(ArrayList<Dependency> dependencies, ArrayList<String> paths, String url) {
 		for(int i = 0; i < dependencies.size(); i++) {

src/io/cubyz/github/GitHubConnection.java

@@ -122,6 +122,7 @@ public static void downloadAndLaunchRelease(File folder) {
 
 		// Build the classpath:
 		ArrayList<String> libs = DependencyManager.fetchDependencies("https://github.com/PixelGuys/Cubyz/releases/download/"+tag+"/pom.xml", System.getProperty("user.home") + "/.cubyz", new File(folder, "pom.xml"));
+
 		// Put it all together as a classpath attribute:
 		char classpathSeperator = OSInfo.OS_FAMILY.equals("windows") ? ';' : ':';
 		String classpath = "";
@@ -132,7 +133,7 @@ public static void downloadAndLaunchRelease(File folder) {
 		classpath += folder.getAbsolutePath()+"/main.jar";
 
 		// Launch it:
-		ProcessBuilder pb = new ProcessBuilder("java", "-cp", classpath, "io.cubyz.client.GameLauncher");
+		ProcessBuilder pb = new ProcessBuilder("java", "-cp", classpath, DependencyManager.findMainClass());
 		pb.directory(folder);
 		pb.redirectOutput(Redirect.INHERIT);
 		pb.redirectError(Redirect.INHERIT);