eZFSFileHandler does not load "datatype" info, and there is no method on eZClusterFileHandlerInterface to retrieve it when it is missing from the internal data format.

1. SPI\IO\BinaryFile->mimeType should be made required so the code loading the file can be removed from IO Service
2. Legacy kernel can either changed to:

• A: Introduce a method on eZClusterFileHandlerInterface to get datatype/mimetype if it is missing from metaData
• B: Change FS handler to set "datatype" on metaData in loadMetaData(), like https://gist.github.com/andrerom/17053187dbfea0a89806

Originally reported by Hakim: http://share.ez.no/forums/ez-publish-5-platform/allowed-memory-size-exhausted