在bolt中访问后端时出现此奇怪错误。我没有删除这个特定的目录，并且frontent工作正常。
Stack trace:
#0 src/Render.php(53): Twig_Loader_Filesystem->addPath('/var/www/html/h...')
#1 src/Application.php(607): Bolt\Render->render('error.twig', Array)
#2 [internal function]: Bolt\Application->errorHandler(Object(Twig_Error_Loader), 500)
#3 vendor/silex/silex/src/Silex/ExceptionListenerWrapper.php(52): call_user_func(Array, Object(Twig_Error_Loader), 500)
#4 [internal function]: Silex\ExceptionListenerWrapper->__invoke(Object(Symfony\Component\HttpKernel\Event\GetResponseForExceptionEvent), 'kernel.exceptio...', Object(Symfony\Component\EventDispatcher\EventDispatcher))
#5 vendor/symfony/event-dispatcher/Symfony/Component/EventDispatcher/EventDispatcher.php(164): call_user_func(Object(Silex\ExceptionListenerWrapper), Object(Sym
File: vendor/twig/twig/lib/Twig/Loader/Filesystem.php
Line: 93