Clarify oscc_file_contents instructions

The 'Do Not Edit' portion is confusing users. Remove it.
Make it explicit that the user needs to update this section.

Change-Id: I1bd00468fdd9c92763ff7996675991eac7d0ef7c

contrib/single_node_ci_data.yaml

@@ -1,4 +1,4 @@
-# See parameter documetation inside ../manifests/single_node_ci.pp
+# See parameter documentation inside ../manifests/single_node_ci.pp
 # Fields commented out have reasonable default values
 
 #vhost_name:
@@ -7,17 +7,17 @@ project_config_repo: http://your-project-config-repo.example.com/project-config-
 #jenkins_username: jenkins
 #jenkins_password:
 jenkins_ssh_private_key: |
-                         -----BEGIN RSA PRIVATE KEY-----
-                         jenkins private key
-                         -----END RSA PRIVATE KEY-----
+  -----BEGIN RSA PRIVATE KEY-----
+  Insert jenkins private key here
+  -----END RSA PRIVATE KEY-----
 jenkins_ssh_public_key:  your-jenkins-public-key-no-whitespace
 #gerrit_server: review.openstack.org
 #gerrit_ssh_host_key:
 gerrit_user: your-gerrit-user
 gerrit_user_ssh_private_key: |
-                             -----BEGIN RSA PRIVATE KEY-----
-                             gerrit private key
-                             -----END RSA PRIVATE KEY-----
+  -----BEGIN RSA PRIVATE KEY-----
+  Insert gerrit private key here
+  -----END RSA PRIVATE KEY-----
 gerrit_user_ssh_public_key: gerrit-public-key-no-whitespace
 git_email: your-email@example.com
 git_name: Your Name
@@ -28,8 +28,11 @@ log_server: logs.example.com
 #zuul_revision: master
 #zuul_git_source_repo: https://git.openstack.org/openstack-infra/zuul
 oscc_file_contents: |
-                    # Do Not Edit - Generated & Managed by Puppet
-                    #
+  # Insert OSCC file contents here as explained in the
+  # documentation so that nodepool is able to
+  # authenticate to your cloud(s)
+  #
+
 mysql_root_password: secret_mysql_root_password
 mysql_nodepool_password: secret_mysql_nodepool_password
 #nodepool_jenkins_target: jenkins1