Switch to Symfony 3 structure

.gitignore

@@ -1,25 +1,20 @@
-# Cache and logs (Symfony2)
-/app/cache/*
-/app/logs/*
-!app/cache/.gitkeep
-!app/logs/.gitkeep
-
-# Cache and logs (Symfony3)
+# Cache, logs & sessions
+/var/*
+!/var/cache
 /var/cache/*
-/var/logs/*
 !var/cache/.gitkeep
+!/var/logs
+/var/logs/*
 !var/logs/.gitkeep
+!/var/sessions
+/var/sessions/*
+!var/sessions/.gitkeep
+!var/SymfonyRequirements.php
 
 # Parameters
 /app/config/parameters.yml
-/app/config/parameters.ini
 
 # Managed by Composer
-/app/bootstrap.php.cache
-/var/bootstrap.php.cache
-/bin/*
-!bin/console
-!bin/symfony_requirements
 /vendor/
 
 # Assets and user uploads