Start support of Symfony4

Dockerfile

@@ -1,4 +1,4 @@
-FROM php:7.0-cli
+FROM php:7.1-cli
 
 MAINTAINER Tobias Munk tobias@diemeisterei.de
 

composer.json

@@ -12,8 +12,13 @@
             "homepage":"http://codegyre.com"
         }
     ],
-    "minimum-stability": "stable",
-
+    "minimum-stability": "beta",
+    "repositories": [
+        {
+            "type": "git",
+            "url": "https://github.com/VolCh/symfony-console-completion"
+        }
+    ],
     "require": {
         "php": ">=5.4.0 <8.0",
         "ext-json": "*",
@@ -24,17 +29,17 @@
         "facebook/webdriver": ">=1.1.3 <2.0",
         "guzzlehttp/guzzle": ">=4.1.4 <7.0",
         "guzzlehttp/psr7": "~1.0",
-        "symfony/finder": ">=2.7 <4.0",
-        "symfony/console": ">=2.7 <4.0",
-        "symfony/event-dispatcher": ">=2.7 <4.0",
-        "symfony/yaml": ">=2.7 <4.0",
-        "symfony/browser-kit": ">=2.7 <4.0",
-        "symfony/css-selector": ">=2.7 <4.0",
-        "symfony/dom-crawler": ">=2.7.5 <4.0",
+        "symfony/finder": ">=2.7 <5.0",
+        "symfony/console": ">=2.7 <5.0",
+        "symfony/event-dispatcher": ">=2.7 <5.0",
+        "symfony/yaml": ">=2.7 <5.0",
+        "symfony/browser-kit": ">=2.7 <5.0",
+        "symfony/css-selector": ">=2.7 <5.0",
+        "symfony/dom-crawler": ">=2.7.5 <5.0",
         "behat/gherkin": "~4.4.0",
         "sebastian/comparator": ">1.1 <3.0",
         "sebastian/diff": ">=1.4 <3.0",
-        "stecman/symfony-console-completion": "^0.7.0"
+        "stecman/symfony-console-completion": "dev-symfony4"
     },
     "require-dev": {
         "monolog/monolog": "~1.8",
@@ -48,7 +53,7 @@
         "predis/predis": "^1.0",
         "squizlabs/php_codesniffer": "~2.0",
         "vlucas/phpdotenv": "^2.4.0",
-        "symfony/process": ">=2.7 <4.0"
+        "symfony/process": ">=2.7 <5.0"
     },
     "suggest": {
         "codeception/specify": "BDD-style code blocks",