Update Twig from 1.35.0 to 1.42.4 (PHP 5.5 is now required!)

This fixes some errors on PHP 7.4 and contains even more fixes
Also bumped PHP version to 5.5 as Twig requires it.

system/libs/Twig/TokenParser/AutoEscapeTokenParser.php

@@ -0,0 +1,88 @@
+<?php
+
+/*
+ * This file is part of Twig.
+ *
+ * (c) Fabien Potencier
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Twig\TokenParser;
+
+use Twig\Error\SyntaxError;
+use Twig\Node\AutoEscapeNode;
+use Twig\Node\Expression\ConstantExpression;
+use Twig\Token;
+
+/**
+ * Marks a section of a template to be escaped or not.
+ *
+ *   {% autoescape true %}
+ *     Everything will be automatically escaped in this block
+ *   {% endautoescape %}
+ *
+ *   {% autoescape false %}
+ *     Everything will be outputed as is in this block
+ *   {% endautoescape %}
+ *
+ *   {% autoescape true js %}
+ *     Everything will be automatically escaped in this block
+ *     using the js escaping strategy
+ *   {% endautoescape %}
+ *
+ * @final
+ */
+class AutoEscapeTokenParser extends AbstractTokenParser
+{
+    public function parse(Token $token)
+    {
+        $lineno = $token->getLine();
+        $stream = $this->parser->getStream();
+
+        if ($stream->test(Token::BLOCK_END_TYPE)) {
+            $value = 'html';
+        } else {
+            $expr = $this->parser->getExpressionParser()->parseExpression();
+            if (!$expr instanceof ConstantExpression) {
+                throw new SyntaxError('An escaping strategy must be a string or a bool.', $stream->getCurrent()->getLine(), $stream->getSourceContext());
+            }
+            $value = $expr->getAttribute('value');
+
+            $compat = true === $value || false === $value;
+
+            if (true === $value) {
+                $value = 'html';
+            }
+
+            if ($compat && $stream->test(Token::NAME_TYPE)) {
+                @trigger_error('Using the autoescape tag with "true" or "false" before the strategy name is deprecated since version 1.21.', E_USER_DEPRECATED);
+
+                if (false === $value) {
+                    throw new SyntaxError('Unexpected escaping strategy as you set autoescaping to false.', $stream->getCurrent()->getLine(), $stream->getSourceContext());
+                }
+
+                $value = $stream->next()->getValue();
+            }
+        }
+
+        $stream->expect(Token::BLOCK_END_TYPE);
+        $body = $this->parser->subparse([$this, 'decideBlockEnd'], true);
+        $stream->expect(Token::BLOCK_END_TYPE);
+
+        return new AutoEscapeNode($value, $body, $lineno, $this->getTag());
+    }
+
+    public function decideBlockEnd(Token $token)
+    {
+        return $token->test('endautoescape');
+    }
+
+    public function getTag()
+    {
+        return 'autoescape';
+    }
+}
+
+class_alias('Twig\TokenParser\AutoEscapeTokenParser', 'Twig_TokenParser_AutoEscape');