KNOX-2936 - knoxcli convert-topology doesn't work with output-path parameter

gateway-server/src/main/java/org/apache/knox/gateway/util/KnoxCLI.java

@@ -2303,7 +2303,7 @@ public class TopologyConverter extends Command {
             + "--descriptor-name (optional) name of descriptor json config file (including .json extension) \n"
             + "--topology-name (optional) topology-name can be use instead of --path option, if used, KnoxCLI will attempt to find topology from deployed topologies.\n"
             + "\t if not provided topology name will be used as descriptor name \n"
-            + "--output-path (optional) output directory to save provider and descriptor config files \n"
+            + "--output-dir (optional) output directory to save provider and descriptor config files \n"
             + "\t if not provided config files will be saved in appropriate Knox config directory \n"
             + "--force (optional) force rewriting of existing files, if not used, command will fail when the configs files with same name already exist. \n"
             + "--cluster (optional) cluster name, required for service discovery \n"

gateway-server/src/main/java/org/apache/knox/gateway/util/TopologyToDescriptor.java

@@ -227,7 +227,9 @@ private void fileCheck(final File file) throws IOException {
               file.getAbsolutePath()));
     }
     /* make sure file and directories are in place */
-    Files.createDirectories(file.toPath().getParent());
+    if (!file.getParentFile().exists()) {
+      Files.createDirectories(file.toPath().getParent());
+    }
     file.createNewFile();
   }