bumped Symfony version to 3.3.15

Author: fabpot

src/Symfony/Component/HttpKernel/Kernel.php

@@ -61,12 +61,12 @@ abstract class Kernel implements KernelInterface, TerminableInterface
 
     private $projectDir;
 
-    const VERSION = '3.3.14';
-    const VERSION_ID = 30314;
+    const VERSION = '3.3.15-DEV';
+    const VERSION_ID = 30315;
     const MAJOR_VERSION = 3;
     const MINOR_VERSION = 3;
-    const RELEASE_VERSION = 14;
-    const EXTRA_VERSION = '';
+    const RELEASE_VERSION = 15;
+    const EXTRA_VERSION = 'DEV';
 
     const END_OF_MAINTENANCE = '01/2018';
     const END_OF_LIFE = '07/2018';