Backports php5.6

.php_cs

@@ -0,0 +1,18 @@
+<?php
+
+$finder = PhpCsFixer\Finder::create()
+    ->notPath('src/Symfony/Component/Translation/Tests/fixtures/resources.php')
+    ->in(__DIR__.DIRECTORY_SEPARATOR."src")
+;
+
+return PhpCsFixer\Config::create()
+    ->setRules([
+        'line_ending' => true,
+        'single_blank_line_at_eof' => true,
+        'class_attributes_separation' => true,
+        'single_line_after_imports' => true,
+        'blank_line_before_statement' => ['statements' => ['return', 'case', 'default', 'foreach']],
+    ])
+    ->setLineEnding("\n")
+    ->setFinder($finder)
+;

PHP5_TRANSPILATION.md

@@ -0,0 +1,20 @@
+# Transpilation from PHP7 code to PHP5.6
+
+To allow this library to run on PHP5.6 the following process was used:
+
+## 1. Install transpilation library and run transpilation
+The library used is: https://packagist.org/packages/janpiet/php-version-transpiler
+Note that it requires PHP7 to run.
+- `composer global require janpiet/php-version-transpiler:dev-master`
+- `php-version-transpiler src src`
+
+## 2. Additional replaces
+The following seems to have been skipped by the transpiler library
+`find ./src/ -type f -print0 | xargs -0 sed -i -r 's/public const/const/g'`
+
+## 3. Code reformatting
+The PHP transpiler uses the Nikic PHP parser and thus does not retain the original formatting of the file. 
+To reduce unnecessary diffs, we run the code through PHP-CS-Fixer. 
+Be aware that this is not perfect and will still result in whitespace changes.
+- `composer global require friendsofphp/php-cs-fixer`
+- `php-cs-fixer fix`

composer.json

@@ -15,11 +15,11 @@
         }
     ],
     "require": {
-        "php": "^7.1",
-        "ext-json": "*"
+        "php": "^5.6",
+        "ext-json": "^1.2"
     },
     "require-dev": {
-        "phpunit/phpunit": "^7",
+        "phpunit/phpunit": "^5.7",
         "php-coveralls/php-coveralls": "^2"
     },
     "suggest": {