Conform to function declaration standards

- declare desc variable
- declare all positional arguments
- set the cmd
- properly handle DOKKU_APP_NAME

subcommands/destroy

@@ -5,14 +5,18 @@ source "$PLUGIN_BASE_PATH/common/functions"
 source "$(dirname "$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)")/functions"
 
 postgres-destroy-cmd() {
-  [[ -z $2 ]] && dokku_log_fail "Please specify a name for the service"
-  verify_service_name "$2"
-  SERVICE="$2"; SERVICE_ROOT="$PLUGIN_DATA_ROOT/$SERVICE"; LINKS_FILE="$SERVICE_ROOT/LINKS"
+  declare desc="delete the $PLUGIN_SERVICE service and stop its container if there are no links left"
+  local cmd="$PLUGIN_COMMAND_PREFIX:destroy" argv=("$@"); [[ ${argv[0]} == "$cmd" ]] && shift 1
+  declare SERVICE="$1" FORCE_DESTROY="$2"
+
+  [[ -z "$SERVICE" ]] && dokku_log_fail "Please specify a name for the service"
+  verify_service_name "$SERVICE"
+  SERVICE_ROOT="$PLUGIN_DATA_ROOT/$SERVICE"; LINKS_FILE="$SERVICE_ROOT/LINKS"
   SERVICE_NAME="$(get_service_name "$SERVICE")"
 
   [[ -s "$LINKS_FILE" ]] && dokku_log_fail "Cannot delete linked service"
 
-  [[ "$3" == "force" ]] && DOKKU_APPS_FORCE_DELETE=1
+  [[ "$FORCE_DESTROY" == "force" ]] && DOKKU_APPS_FORCE_DELETE=1
   if [[ -z "$DOKKU_APPS_FORCE_DELETE" ]]; then
     dokku_log_warn "WARNING: Potentially Destructive Action"
     dokku_log_warn "This command will destroy $SERVICE $PLUGIN_SERVICE service."
@@ -28,6 +32,7 @@ postgres-destroy-cmd() {
 
   dokku_log_info1 "Deleting $SERVICE"
   if [[ -n $(docker ps -aq -f name="$SERVICE_NAME") ]]; then
+    dokku_log_verbose_quiet "Deleting container data"
     service_stop "$SERVICE"
     sleep 1