Update header.php

added save.handler check for non mongo extension feature with file handler
Update header.php
Update File.php

added cache for data files
Update config.default.php

added example for save.handler.file and save.handler.filename
Update FileTest.php

modified test to work again with the real cache folder
Update FileTest.php
Update FileTest.php
changed fileSaver behaviour again
modified example
codestyle
Merge pull request #114 from sebbrandt87/master

Added a real saveHandler possibilty