Allow bin/aphlict to start without a valid database connection

Summary:
Ref T11818. See that task for a description.

This is like a tiny pinch of hackiness but not really unreasonable. Basically, `aphlict` is already an "uber-server" and one copy can handle a ton of instances.

Test Plan: Started `bin/aphlict` without a valid database connection.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T11818

Differential Revision: https://secure.phabricator.com/D16854

scripts/init/init-aphlict.php

@@ -0,0 +1,10 @@
+<?php
+
+require_once dirname(__FILE__).'/lib.php';
+
+init_phabricator_script(
+  array(
+    // NOTE: We allow aphlict to start with no database, because it's
+    // reasonable to isolate the notification server from other hosts.
+    'config.optional' => true,
+  ));

support/aphlict/server/aphlict_launcher.php

@@ -2,7 +2,7 @@
 <?php
 
 $root = dirname(dirname(dirname(dirname(__FILE__))));
-require_once $root.'/scripts/__init_script__.php';
+require_once $root.'/scripts/init/init-aphlict.php';
 
 PhabricatorAphlictManagementWorkflow::requireExtensions();