Remove "<2.7" constraint on symfony/console

Author: nicolas-grekas

composer.json

@@ -10,7 +10,7 @@
   "require": {
     "php": "~5.5.0|~5.6.0|~7.0.0",
     "composer/composer": "1.0.0-beta1",
-    "symfony/console": "~2.3 <2.7"
+    "symfony/console": "~2.3"
   },
   "require-dev": {
     "phpunit/phpunit": "4.1.0"