Call setMetadataFiltered(true) for all Memoizer uses

The fact that OMEROWrapper was using `setMetadataFilter(true)`
but the `PixelsService` was not led to the `equalReaders` method
to return false which essentially deactivated Memoizer speed
ups for `resetDefaultsInSet`!

The primary result of this is that during `IRenderingSettings.resetDefaultsInSet()` a new memoizer file should not be generated. `loci.formats.Memoizer` logging at `DEBUG` should be checked for the import of a simple file (like PNG).

/cc @jburel @melissalinkert

This is also a related cause of the file leak seen in openmicroscopy/bioformats#1196