chore: Add NSP gitops with sa customization (vmware-tanzu#296)

Signed-off-by: Diego Alfonso <dalfonso@vmware.com>

ns-provisioner-samples/gitops-install-params-sa/desired-namespaces.yaml

@@ -0,0 +1,10 @@
+#@data/values
+---
+namespaces:
+#! The only required parameter is the name of the namespace. All additional values provided here 
+#! for a namespace will be available under data.values for templating additional sources
+- name: dev
+ supply_chain_service_account:
+ secrets:
+ - git
+- name: qa

ns-provisioner-samples/gitops-install-params-sa/namespaces.yaml

@@ -0,0 +1,11 @@
+#@ load("@ytt:data", "data")
+#! This for loop will loop over the namespace list in desired-namespaces.yaml and will create those namespaces.
+#! NOTE: if you have another tool like Tanzu Mission Control or some other process that is taking care of creating namespaces for you, 
+#! and you don’t want namespace provisioner to create the namespaces, you can delete this file from your GitOps install repository.
+#@ for ns in data.values.namespaces:
+---
+apiVersion: v1
+kind: Namespace
+metadata:
+ name: #@ ns.name
+#@ end