INF-184 - Support the reverse proxy mode

- Switch the reverse proxy mode by var

Change-Id: I03c159ab0863eb935ed1b20fe6ec62a924d59aef
diff --git a/defaults/main.yml b/defaults/main.yml
index 57b65e7..88f7449 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -6,6 +6,7 @@
 #
 keycloak_java_version: 11
 
+keycloak_behind_reverse_proxy: true
 keycloak_server: "http://localhost:8080"
 keycloak_admin_api: "{{ keycloak_server }}/auth/admin/realms/master"
 keycloak_username: "keycloak"