TMI-85: Support 16 bit signed int data

imageio/imageio-metadata/src/main/java/com/twelvemonkeys/imageio/metadata/exif/EXIFEntry.java

@@ -140,6 +140,8 @@ final class EXIFEntry extends AbstractEntry {
                 return "ColorMap";
             case TIFF.TAG_EXTRA_SAMPLES:
                 return "ExtraSamples";
+            case TIFF.TAG_SAMPLE_FORMAT:
+                return "SampleFormat";
 
             case TIFF.TAG_SUB_IFD:
                 return "SubIFD";