Merge pull request #2 from tchemineau/master

Try to create the cache directory before throwing an exception
Fix errors in README
allow to set cache option to false

Allowed posibility to disable cache in options like here: http://twig.sensiolabs.org/doc/api.html#environment-options
Merge pull request #3 from Skorney/master

allow to set cache option to false
Merge remote-tracking branch 'upstream/master'