renamed private.go to tag_private.go to line up with baseline and extended
Added tags for DNG versions 1.0 - 1.4
Improvement to String() method printing for a Field.
Removing tags from the Private tag space that have been accounted for in other packages
Improving error messages for parsing of tiff files and ifds.
Adding URL references for geotiff
Adding comments to tiff85
Adding tags for geotiff
Adding modi package for Microsoft Office Document Imaging tag support