minor #48 Allow Symfony 5.0 (nicolas-grekas)

This PR was merged into the 3.0-dev branch.

Discussion
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Allow Symfony 5.0

Commits
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41efff3 Allow Symfony 5.0

Author: nicolas-grekas

composer.json

@@ -17,10 +17,10 @@
     ],
     "require": {
         "php": ">=5.5.9",
-        "symfony/security-core": "~2.8|~3.0|~4.0"
+        "symfony/security-core": "^2.8|^3.0|^4.0|^5.0"
     },
     "require-dev": {
-        "symfony/phpunit-bridge": "~2.8|~3.0|~4.0",
+        "symfony/phpunit-bridge": "^2.8|^3.0|^4.0|^5.0",
         "doctrine/common": "~2.2",
         "doctrine/dbal": "~2.2",
         "psr/log": "~1.0"