Replace java.awt.image.ColorModel with net.imglib2.display.ColorTable

[hinerm]

In the SCIFIO Writers (and corresponding SCIFIOConfig) we attach java.awt.image.ColorModels. These seem only to be used in the code as LUTs, e.g. when instanceof IndexedColorTable in APNG, AVI, JPEG2k and TIFF formats.

I think this was a historical left over from Bio-Formats originally being written against java.awt.image.BufferedImages, before migrating to byte[].

In SCIFIO, our LUT standard is the net.imglib2.display.ColorTable. Writers for formats with LUTs should therefore be pulling ColorTables off A) the provided Plane objects, or B) the Writer's attached Metadata.

The corresponding SCIFIOConfig#writerXXXColorModel methods should be similarly updated to take ColorTable objects.