Update composer.json with minimal Symfony3 requeriments

Author: terox

composer.json

@@ -1,4 +1,4 @@
-{  
+{
     "name":"vivait/string-generator-bundle",
     "license": "MIT",
     "description":"Generate random strings for IDs or keys using property annotations",
@@ -11,11 +11,11 @@
     "minimum-stability": "dev",
     "prefer-stable": true,
     "require": {
-        "php": ">=5.3.3",
+        "php": ">=5.5.3",
         "doctrine/common": "~2.2",
         "doctrine/orm": "~2.2",
-        "symfony/security": "~2.1",
-        "symfony/options-resolver": "~2.1",
+        "symfony/security": "~2.8|~3.2",
+        "symfony/options-resolver": "~2.8|~3.2",
         "ircmaxell/random-lib": "~1.0"
     },
     "require-dev": {