[DOC] Update London OOM documentation

Add information:
- new Deployment options (Production, Development)
- move Istio deployment to base installation
- add Gateway-API and Keycloak Installation instructions
- split and rename of a few files for updated structure
- changed rst section formatting as suggested in sphinx rtd theme
- add London Release Notes

Issue-ID: OOM-3159

Signed-off-by: Andreas Geissler <andreas-geissler@telekom.de>
Change-Id: I98b8541d51daba982fd6c8be0c85fae676d53c13
diff --git a/docs/sections/resources/yaml/istiod.yaml b/docs/sections/resources/yaml/istiod.yaml
new file mode 100644
index 0000000..4738012
--- /dev/null
+++ b/docs/sections/resources/yaml/istiod.yaml
@@ -0,0 +1,21 @@
+global:
+  proxy:
+    # Controls if sidecar is injected at the front of the container list and blocks the start of the other containers until the proxy is ready
+    holdApplicationUntilProxyStarts: true
+  #logging:
+  #  level: "default:debug"
+meshConfig:
+  rootNamespace: istio-config
+  extensionProviders:
+  - name: oauth2-proxy
+    envoyExtAuthzHttp:
+      service: oauth2-proxy.default.svc.cluster.local
+      port: 80
+      timeout: 1.5s
+      includeHeadersInCheck: ["authorization", "cookie"]
+      headersToUpstreamOnAllow: ["x-forwarded-access-token", "authorization", "path", "x-auth-request-user", "x-auth-request-email", "x-auth-request-access-token"]
+      headersToDownstreamOnDeny: ["content-type", "set-cookie"]
+pilot:
+  env:
+    PILOT_ENABLE_MYSQL_FILTER: true
+    PILOT_HTTP10: true
\ No newline at end of file
diff --git a/docs/sections/resources/yaml/keycloak-db-values.yaml b/docs/sections/resources/yaml/keycloak-db-values.yaml
new file mode 100644
index 0000000..ae1459b
--- /dev/null
+++ b/docs/sections/resources/yaml/keycloak-db-values.yaml
@@ -0,0 +1,7 @@
+# See https://github.com/bitnami/charts/tree/master/bitnami/postgresql
+global:
+  postgresql:
+    auth:
+      username: dbusername
+      password: dbpassword
+      database: keycloak
\ No newline at end of file
diff --git a/docs/sections/resources/yaml/keycloak-server-values.yaml b/docs/sections/resources/yaml/keycloak-server-values.yaml
new file mode 100644
index 0000000..7eaecbe
--- /dev/null
+++ b/docs/sections/resources/yaml/keycloak-server-values.yaml
@@ -0,0 +1,53 @@
+image:
+  # The Keycloak image repository
+  repository: quay.io/keycloak/keycloak
+  # Overrides the Keycloak image tag whose default is the chart appVersion
+  tag: "19.0.3-legacy"
+
+postgresql:
+  # If `true`, the Postgresql dependency is enabled
+  enabled: false
+
+extraEnv: |
+  - name: KEYCLOAK_USER
+    valueFrom:
+      secretKeyRef:
+        name: {{ include "keycloak.fullname" . }}-admin-creds
+        key: user
+  - name: KEYCLOAK_PASSWORD
+    valueFrom:
+      secretKeyRef:
+        name: {{ include "keycloak.fullname" . }}-admin-creds
+        key: password
+  - name: DB_VENDOR
+    value: postgres
+  - name: DB_ADDR
+    value: keycloak-db-postgresql
+  - name: DB_PORT
+    value: "5432"
+  - name: DB_DATABASE
+    value: keycloak
+  - name: DB_USER
+    value: dbusername
+  - name: DB_PASSWORD_FILE
+    value: /secrets/db-creds/password
+  - name: PROXY_ADDRESS_FORWARDING
+    value: "true"
+
+extraVolumeMounts: |
+  - name: db-creds
+    mountPath: /secrets/db-creds
+    readOnly: true
+
+extraVolumes: |
+  - name: db-creds
+    secret:
+      secretName: keycloak-db-postgresql
+
+secrets:
+  admin-creds:
+    annotations:
+      my-test-annotation: Test secret for {{ include "keycloak.fullname" . }}
+    stringData:
+      user: admin
+      password: secret
\ No newline at end of file