Import latest app updates from streamline

An updated set of source files and initialization was provided by streamline to
address issues observed during initial testing. These files have been updated in
order to generate a new set of app images.

docker/streamline-src/vendor/symfony/error-handler/README.md

@@ -1,44 +0,0 @@
-ErrorHandler Component
-======================
-
-The ErrorHandler component provides tools to manage errors and ease debugging PHP code.
-
-Getting Started
----------------
-
-```
-$ composer require symfony/error-handler
-```
-
-```php
-use Symfony\Component\ErrorHandler\Debug;
-use Symfony\Component\ErrorHandler\ErrorHandler;
-use Symfony\Component\ErrorHandler\DebugClassLoader;
-
-Debug::enable();
-
-// or enable only one feature
-//ErrorHandler::register();
-//DebugClassLoader::enable();
-
-// If you want a custom generic template when debug is not enabled
-// HtmlErrorRenderer::setTemplate('/path/to/custom/error.html.php');
-
-$data = ErrorHandler::call(static function () use ($filename, $datetimeFormat) {
-    // if any code executed inside this anonymous function fails, a PHP exception
-    // will be thrown, even if the code uses the '@' PHP silence operator
-    $data = json_decode(file_get_contents($filename), true);
-    $data['read_at'] = date($datetimeFormat);
-    file_put_contents($filename, json_encode($data));
-
-    return $data;
-});
-```
-
-Resources
----------
-
- * [Contributing](https://symfony.com/doc/current/contributing/index.html)
- * [Report issues](https://github.com/symfony/symfony/issues) and
-   [send Pull Requests](https://github.com/symfony/symfony/pulls)
-   in the [main Symfony repository](https://github.com/symfony/symfony)