adding stream functions to filestore

git-svn-id: https://svn.muze.nl/svn/ariadne-php5/trunk@5687 7882d7ee-46e0-0310-a255-a28a61b628e4
use stream api instead of making a copy of the file twice

git-svn-id: https://svn.muze.nl/svn/ariadne-php5/trunk@5688 7882d7ee-46e0-0310-a255-a28a61b628e4