Add preserve-ns in README.md

Author: suvaanshkumar

README.md

@@ -110,6 +110,7 @@ Usage:
 | -original-name            | Use the object's original name instead of adding the chart's release name as the common prefix.                                                                                                             | `helmify -original-name`            |
 | -cert-manager-as-subchart | Allows the user to install cert-manager as a subchart                                                                                                                                                       | `helmify -cert-manager-as-subchart` |
 | -cert-manager-version     | Allows the user to specify cert-manager subchart version. Only useful with cert-manager-as-subchart. (default "v1.12.2")                                                                                    | `helmify -cert-manager-as-subchart` |
+| -preserve-ns              | Allows users to use the object's original namespace instead of adding all the resources to a common namespace. (default "false")                                                                                    | `helmify -preserve-ns` |
 ## Status
 Supported k8s resources:
 - Deployment, DaemonSet, StatefulSet