SP-452 BIS-297 Add reading color depth to image readers

...urce/java/ch/systemsx/cisd/imagereaders/IImageReader.java

...sx/cisd/imagereaders/bioformats/BioFormatsImageUtils.java

...imagereaders/bioformats/DefaultBioformatsImageReader.java

...ch/systemsx/cisd/imagereaders/ij/ImageJReaderLibrary.java

...temsx/cisd/imagereaders/imageio/ImageIOReaderLibrary.java

...ch/systemsx/cisd/imagereaders/jai/DefaultImageReader.java

.../imagereaders/bioformats/BioFormatsReaderLibraryTest.java

...ystemsx/cisd/imagereaders/ij/ImageJReaderLibraryTest.java

...x/cisd/imagereaders/imageio/ImageIOReaderLibraryTest.java

...ystemsx/cisd/imagereaders/jai/DefaultImageReaderTest.java