create functions for app/global vhost detection. make VHOST setting more explicit

plugins/nginx-vhosts/post-deploy

@@ -1,15 +1,12 @@
 #!/usr/bin/env bash
 set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 source "$PLUGIN_CORE_AVAILABLE_PATH/common/functions"
-source "$PLUGIN_AVAILABLE_PATH/config/functions"
 source "$PLUGIN_AVAILABLE_PATH/nginx-vhosts/functions"
 
 APP="$1"
 if [[ -f "$DOKKU_ROOT/$APP/IP.web.1" ]] && [[ -f "$DOKKU_ROOT/$APP/PORT.web.1" ]]; then
-  NO_VHOST=$(config_get $APP NO_VHOST || true)
-
-  if [[ -n "$NO_VHOST" ]]; then
-    dokku_log_info1 "NO_VHOST config detected"
+  if [[ "$(is_app_vhost_enabled $APP)" == "false" ]]; then
+    dokku_log_info1 "VHOST support disabled. Skipping domains setup"
   elif [[ ! -f "$DOKKU_ROOT/$APP/VHOST" ]]; then
     dokku domains:setup $APP
   fi