Update kubectl Installer for NS Mode & Doc Change

Added a NAMESPACE_MODE environment variable to the kubectl installer.
This env var configures the 'namespace_mode' variable in the Ansible
installer, therefore determining which Cluster Roles are installed to
enable the desired namespace functionality.

Also includes an update to the headers describing the various namespace
modes in the namespace documentation.

Author: andrewlecuyer

docs/content/architecture/namespace.md

@@ -107,7 +107,7 @@ enabled for the Operator installation.  Please consult the installation guides f
 installation methods available to determine the settings required to install the `ClusterRoles`
 required for each mode.
 
-### dynamic
+### `dynamic`
 
 Enables full dynamic namespace capabilities, in which the Operator can create, delete and update
 any namespaces within the Kubernetes cluster, while then also having the ability to create the 
@@ -167,7 +167,7 @@ rules:
       - delete
 ```
 
-### readonly
+### `readonly`
 
 In this mode the PostgreSQL Operator is still able to listen for  namespace events within the 
 Kubernetetes cluster, and then create and run and/or remove controllers as namespaces are added,
@@ -194,7 +194,7 @@ rules:
       - watch
 ```
 
-### disabled
+### `disabled`
 
 Disables namespace capabilities within the Operator altogether.  While in this mode the Operator
 will simply attempt to work with the target namespaces specified during installation.  If no 

installers/ansible/inventory

@@ -95,7 +95,7 @@ create_rbac='true'
 # them.  And finally "disabled" prevents the creation of any Cluster Roles,
 # and therefore disables all namespace functionality.
 # ==================
-# namespace_mode='disabled'
+# namespace_mode='dynamic'
 
 # ===================
 # PGO Client Container Settings

installers/image/inventory_template

@@ -18,6 +18,22 @@ kubernetes_in_cluster='$KUBERNETES_IN_CLUSTER'
 # ==================
 create_rbac='$CREATE_RBAC'
 
+# Namespace Mode
+# ==================
+# Note: this setting is only applicable if 'create_rbac=true'.
+# 
+# When installing RBAC using 'create_rbac', the namespace mode determines
+# what Cluster Roles are installed.  The default mode if a value is not 
+# specified here is "dynamic", which gives the Operator the full set of 
+# Cluster Roles to create/modify/delete namespaces, and also install RBAC
+# within those namespaces in order to create PG clusters.  A value of 
+# "readonly" can also be specified, which allows the Operator to view 
+# namespaces, but not create/modify/delete them nor create  RBAC within 
+# them.  And finally "disabled" prevents the creation of any Cluster Roles,
+# and therefore disables all namespace functionality.
+# ==================
+namespace_mode='$NAMESPACE_MODE'
+
 # ===================
 # PGO Client Container Settings
 # The following settings configure the deployment of a PGO Client Container

installers/method/kubectl/full_options

@@ -8,6 +8,8 @@ value: "false"
 value: "true"
 - name: CREATE_RBAC
 value: "true"
+- name: NAMESPACE_MODE
+value: "dynamic"
 - name: PGO_INSTALLATION_NAME
 value: "devtest"
 - name: PGO_ADMIN_USERNAME

installers/method/kubectl/install.yml

@@ -53,6 +53,8 @@ spec:
                     value: "true"
                   - name: CREATE_RBAC
                     value: "true"
+                  - name: NAMESPACE_MODE
+                    value: "dynamic"
                   - name: PGO_INSTALLATION_NAME
                     value: "devtest"
                   - name: PGO_ADMIN_USERNAME

installers/method/kubectl/uninstall.yml

@@ -53,6 +53,8 @@ spec:
                     value: "true"
                   - name: CREATE_RBAC
                     value: "true"
+                  - name: NAMESPACE_MODE
+                    value: "dynamic"
                   - name: PGO_INSTALLATION_NAME
                     value: "devtest"
                   - name: PGO_ADMIN_USERNAME

installers/method/kubectl/update.yml

@@ -53,6 +53,8 @@ spec:
                     value: "true"
                   - name: CREATE_RBAC
                     value: "true"
+                  - name: NAMESPACE_MODE
+                    value: "dynamic"
                   - name: PGO_INSTALLATION_NAME
                     value: "devtest"
                   - name: PGO_ADMIN_USERNAME