Fixed how NativeQT bpp are populated

The ImageMetadata can bases its bits per pixels purely on pixel type.
Also modified the translator bpp calculation so that rgb and pixel type
are both derived properly.
Added signatures for populating ImageMetadata

SCIFIOMetadataTools now has more options for populating Metadata,
including the ability to automatically look up bits per pixel of a given
pixel type.
AbstractMetadata only resets SCIFIO fields

The AbstractMetadata method will now only reset instances of
ome.scifio.Field.
ChannelSeparator checks plane compatibility

Was mistakenly using the ReaderFilter#isCompatible method, which
determines if the Filter is capable of wrapping the given object (e.g. a
Reader) and thus would always be false when testing a plane.

Now just test to see if it's an instance of a ByteArrayPlane.
Corrected image/plane index swap

One of the openPlane signatures in ChannelSeparator was swapping its
ImageIndex and planeIndex, leading to impossible to open planes.
Added size calculations to Metadata

ImageMetadata can now report its estimated size. Correspondingly,
Metadata can now report the size of a specific image, or of the complete
dataset.
SCIFIO beta versioning and groupId

Updated the SCIFIO (scifio-devel component) groupId to be "scifio", and
version to "0.1.0-SNAPSHOT". These are beta versions and subject to
change (and rebasing).

Dependencies updated as appropriate.