ENH: Adding initial implementation for Transform class

This class is based on work done on an old topic and has been
restored. It wraps many ITK transforms in a pimple implementation,
with a minimal exposure of interface to SimpleITK.
ENH: enable copy on write and shallow copying
ENH: adding AddTransform method to Transform class

This method add transforms together to form a composite transform.
ENH: a composite transform is constructed with a identity transform

Previously the composite transform was constructed as empty. This may
cause some problems with filters and registration, so it's now
initialized with an identity transform.
Adding reading and writing to transformations
Adding first basic test for transfomations
Corrected Deep Copy to use Clone, improved composite initialization
fix typeo in function name
Adding methods to set transform fixed parameters
Throw exception for 3D only transforms

Adding explicit implementation for some implicit pimple transform
methods.
Adding tests for Transform class
enable registation of transform factories

The Transform IO factorys are implicitly registered when the reader
and writer are included in a translation unit. So, these headers are
added to a cxx file sitk's IO library.
Adding Transform test for AddTransform method
DOC: another pass at Transform doxygen
Corrected loading of composite transform

Special handling is needed for the case of composite transforms. They
are reported by the reader as a file with multiple transforms with the
first being the composite.
Adding support for transfroms to the resample filter

The sitkTransfom.h file is added to the BasicFilters header
temporarily just for the resample filter, untill a more localized
solution can be implemented.
Adding test for reading and resampling with transforms
Adding transform method to transform a point
Merge branch 'UpdateDataSubmodule' into SIMPLEITK-264_AddTransformations
Adding test for tranformation of points