fixed #4552: Zend\Cache\Storage\Adapter\Wincache::getItem() have to return NULL in cases of not found items
Merge pull request #4632 from marc-mabe/hotfix/4552

fixed #4552: Wincache::getItem() have to return NULL in cases of missing items
Merge branch 'hotfix/4632'

Close #4632
Fixes #4552