Mkdir permissions issue

[zquintana]

To begin with let me say great bundle. Thanks!

I found an issue while using this bundle for a large project. The problem is that by default stash tries to create a directory in /tmp/stash. This directory isn't always writable. As a result, it will create a fatal error and stop all Symfony execution. Anyway we can change that?

[magnusnordlander]

This is ostensibly configurable using the path option of FileSystem, but without #78 you may run in to issues anyway.