Make vtkDICOMMetaData into a subclass of vtkDataObject.
Add a vtkDICOMWriter class for writing DICOM images.

For now, this supports only one SOP storage class:
1.2.840.10008.5.1.4.1.1.7    Secondary Capture
Fix writing of RGB files.
Add code to compiler for writing byte-swapped frames.
Don't automatically reverse slice order when flipping images.

Slice order should only be reversed if the reader had to reverse
the original slices while reading the original image.
Fix commit from yesterday: free the buf that I new.
Add the vtkDICOMGenerator class for instantiating DICOM data objects.
Add reader support for SliceLocationVector.
Fix method comments to help doxygen.
Copy palette from source data if type is PALETTE COLOR.
Add the GeneralEquipment and ImagePlane modules.

The GeneralEquipment module is straightforward, but the ImagePlane
module will have to take care of items like whether the image rows
are bottom-to-top (as most VTK images are).
Fix the Secondary Capture SOP UIDs written to the files.
Add a DICOM generator for MR images.  Far from complete.
Centralize the copying of attributes in the generator.
Add an array to keep track of file-to-slice mapping when writing.
Move functional groups into a separate thread for now.

Supporting the Functional Groups Module and the enhanced MR/CT/PET files
is going to require a lot of work, move it into a separate thread until
the non-enhanced MR module is solid.
Add the clinical trial modules as optional.
List DICOM modules in order to make it easier to audit SOPs.
Add the DICOM device and specimen modules as optional.
Put ImagePixel and ImagePlane into same order as standard.