feat(util/FileUtil): add method for recursive folder copy

src/main/java/de/hftstuttgart/utils/FileUtil.java

 package de.hftstuttgart.utils;
 
 import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
 
 /**
  * Helper Class for all file related tasks.
@@ -27,4 +30,14 @@ public class FileUtil {
         folder.delete();
     }
 
+    public static void copyFolder(Path src, Path dst) throws IOException {
+        Files.walk(src)
+            .forEach(source -> {
+                try {
+                    Files.copy(source, dst.resolve(src.relativize(source)));
+                } catch (IOException e) {
+                    throw new RuntimeException(e.getMessage(), e);
+                }
+            });
+    }
 }